16991768 has 8 divisors (see below), whose sum is σ = 31859580. Its totient is φ = 8495880.

The previous prime is 16991759. The next prime is 16991773. The reversal of 16991768 is 86719961.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1061978 + ... + 1061993.

Almost surely, 2^16991768 is an apocalyptic number.

It is an amenable number.

16991768 is a deficient number, since it is larger than the sum of its proper divisors (14867812).

16991768 is a wasteful number, since it uses less digits than its factorization.

16991768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2123977 (or 2123973 counting only the distinct ones).

The product of its digits is 163296, while the sum is 47.

The square root of 16991768 is about 4122.1072281055. The cubic root of 16991768 is about 257.0866488550.

The spelling of 16991768 in words is "sixteen million, nine hundred ninety-one thousand, seven hundred sixty-eight".