16556701565172 has 12 divisors (see below), whose sum is σ = 38632303652096. Its totient is φ = 5518900521720.

The previous prime is 16556701565171. The next prime is 16556701565189. The reversal of 16556701565172 is 27156510765561.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16556701565171) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 689862565204 + ... + 689862565227.

Almost surely, 2^{16556701565172} is an apocalyptic number.

16556701565172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

16556701565172 is an abundant number, since it is smaller than the sum of its proper divisors (22075602086924).

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

16556701565172 is a wasteful number, since it uses less digits than its factorization.

16556701565172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1379725130438 (or 1379725130436 counting only the distinct ones).

The product of its (nonzero) digits is 13230000, while the sum is 57.

The spelling of 16556701565172 in words is "sixteen trillion, five hundred fifty-six billion, seven hundred one million, five hundred sixty-five thousand, one hundred seventy-two".