1690881 has 16 divisors (see below), whose sum is σ = 2358720. Its totient is φ = 1076480.

The previous prime is 1690853. The next prime is 1690883. The reversal of 1690881 is 1880961.

It is a cyclic number.

It is not a de Polignac number, because 1690881 - 2⁵ = 1690849 is a prime.

It is a super-2 number, since 2×1690881² = 5718157112322, which contains 22 as substring.

1690881 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1690883) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7141 + ... + 7373.

It is an arithmetic number, because the mean of its divisors is an integer number (147420).

2^1690881 is an apocalyptic number.

It is an amenable number.

1690881 is a deficient number, since it is larger than the sum of its proper divisors (667839).

1690881 is a wasteful number, since it uses less digits than its factorization.

1690881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336.

The product of its (nonzero) digits is 3456, while the sum is 33.

The square root of 1690881 is about 1300.3388020051. The cubic root of 1690881 is about 119.1345370099.

The spelling of 1690881 in words is "one million, six hundred ninety thousand, eight hundred eighty-one".