Subtracting from 1690 its reverse (961), we obtain a 6-th power (729 = 36).
1690 is an esthetic number in base 8, because in such base its adjacent digits differ by 1.
It is an alternating number because its digits alternate between odd and even.
1690 is an undulating number in base 8.
It is a plaindrome in base 9, base 14, base 15 and base 16.
It is a nialpdrome in base 13.
It is a zygodrome in base 9.
21690 is an apocalyptic number.
1690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.
1690 is a wasteful number, since it uses less digits than its factorization.
1690 is an evil number, because the sum of its binary digits is even.
The square root of 1690 is about 41.1096095822. The cubic root of 1690 is about 11.9113842520.
The spelling of 1690 in words is "one thousand, six hundred ninety".