21712157067128 has 16 divisors (see below), whose sum is σ = 44411230364760. Its totient is φ = 9869162303200.

The previous prime is 21712157067121. The next prime is 21712157067163. The reversal of 21712157067128 is 82176075121712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21712157067121) 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, 123364528703 + ... + 123364528878.

Almost surely, 2^{21712157067128} is an apocalyptic number.

It is an amenable number.

21712157067128 is an abundant number, since it is smaller than the sum of its proper divisors (22699073297632).

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

21712157067128 is a wasteful number, since it uses less digits than its factorization.

21712157067128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246729057598 (or 246729057594 counting only the distinct ones).

The product of its (nonzero) digits is 658560, while the sum is 50.

The spelling of 21712157067128 in words is "twenty-one trillion, seven hundred twelve billion, one hundred fifty-seven million, sixty-seven thousand, one hundred twenty-eight".