21161055712 has 24 divisors (see below), whose sum is σ = 41750837856. Its totient is φ = 10557668352.

The previous prime is 21161055701. The next prime is 21161055739. The reversal of 21161055712 is 21755016112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 699313 + ... + 728944.

It is an arithmetic number, because the mean of its divisors is an integer number (1739618244).

Almost surely, 2^21161055712 is an apocalyptic number.

It is an amenable number.

21161055712 is a deficient number, since it is larger than the sum of its proper divisors (20589782144).

21161055712 is a wasteful number, since it uses less digits than its factorization.

21161055712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1428730 (or 1428722 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 31.

The spelling of 21161055712 in words is "twenty-one billion, one hundred sixty-one million, fifty-five thousand, seven hundred twelve".