21715125423138 has 96 divisors (see below), whose sum is σ = 54872507289600. Its totient is φ = 6203828816640.

The previous prime is 21715125423109. The next prime is 21715125423143. The reversal of 21715125423138 is 83132452151712.

21715125423138 is a `hidden beast` number, since 2 + 1 + 71 + 5 + 1 + 2 + 542 + 3 + 1 + 38 = 666.

It is a super-2 number, since 2×21715125423138² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21715125423093 and 21715125423102.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 81468703 + ... + 81734813.

It is an arithmetic number, because the mean of its divisors is an integer number (571588617600).

Almost surely, 2^{21715125423138} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21715125423138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27436253644800).

21715125423138 is an abundant number, since it is smaller than the sum of its proper divisors (33157381866462).

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

21715125423138 is a wasteful number, since it uses less digits than its factorization.

21715125423138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 279357 (or 279340 counting only the distinct ones).

The product of its digits is 403200, while the sum is 45.

The spelling of 21715125423138 in words is "twenty-one trillion, seven hundred fifteen billion, one hundred twenty-five million, four hundred twenty-three thousand, one hundred thirty-eight".