21356151572 has 36 divisors (see below), whose sum is σ = 43487680320. Its totient is φ = 9149971824.

The previous prime is 21356151571. The next prime is 21356151611. The reversal of 21356151572 is 27515165312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21356151571) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 754223 + ... + 782025.

It is an arithmetic number, because the mean of its divisors is an integer number (1207991120).

Almost surely, 2^21356151572 is an apocalyptic number.

It is an amenable number.

21356151572 is an abundant number, since it is smaller than the sum of its proper divisors (22131528748).

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

21356151572 is a wasteful number, since it uses less digits than its factorization.

21356151572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31740 (or 31731 counting only the distinct ones).

The product of its digits is 63000, while the sum is 38.

The spelling of 21356151572 in words is "twenty-one billion, three hundred fifty-six million, one hundred fifty-one thousand, five hundred seventy-two".