16691656 has 8 divisors (see below), whose sum is σ = 31296870. Its totient is φ = 8345824.

The previous prime is 16691651. The next prime is 16691657. The reversal of 16691656 is 65619661.

It can be written as a sum of positive squares in only one way, i.e., 12489156 + 4202500 = 3534^2 + 2050^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×16691656² = 557222760044672, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (16691651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1043221 + ... + 1043236.

Almost surely, 2^16691656 is an apocalyptic number.

It is an amenable number.

16691656 is a deficient number, since it is larger than the sum of its proper divisors (14605214).

16691656 is a wasteful number, since it uses less digits than its factorization.

16691656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2086463 (or 2086459 counting only the distinct ones).

The product of its digits is 58320, while the sum is 40.

The square root of 16691656 is about 4085.5423140631. The cubic root of 16691656 is about 255.5640774586.

The spelling of 16691656 in words is "sixteen million, six hundred ninety-one thousand, six hundred fifty-six".