16991688 has 32 divisors (see below), whose sum is σ = 48548160. Its totient is φ = 4854720.

The previous prime is 16991659. The next prime is 16991701. The reversal of 16991688 is 88619961.

It is a super-2 number, since 2×16991688² = 577434922178688, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50403 + ... + 50738.

It is an arithmetic number, because the mean of its divisors is an integer number (1517130).

Almost surely, 2^16991688 is an apocalyptic number.

It is an amenable number.

16991688 is an abundant number, since it is smaller than the sum of its proper divisors (31556472).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16991688 is a wasteful number, since it uses less digits than its factorization.

16991688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101157 (or 101153 counting only the distinct ones).

The product of its digits is 186624, while the sum is 48.

The square root of 16991688 is about 4122.0975243194. The cubic root of 16991688 is about 257.0862453858.

The spelling of 16991688 in words is "sixteen million, nine hundred ninety-one thousand, six hundred eighty-eight".