How to remove <int> <num> <num> <num> <num> <num> in a table

library(data.table)
dt <- data.table(x = 1:5, y = 11:15)
dt
#       x     y
#   <int> <int>
#1:     1    11
#2:     2    12
#3:     3    13
#4:     4    14
#5:     5    15

print(dt, class = FALSE, row.names = FALSE)
# x  y
# 1 11
# 2 12
# 3 13
# 4 14
# 5 15

library(data.table)
options(datatable.print.class=FALSE)
data.table(a=1:2, b=pi + 0+1)
#    a        b
# 1: 1 4.141593
# 2: 2 4.141593
options(datatable.print.class=TRUE)
data.table(a=1:2, b=pi + 0+1)
#        a        b
#    <int>    <num>
# 1:     1 4.141593
# 2:     2 4.141593