21572525520 has 1440 divisors, whose sum is σ = 99685048320. Its totient is φ = 4075868160.

The previous prime is 21572525509. The next prime is 21572525521. The reversal of 21572525520 is 2552527512.

21572525520 is a `hidden beast` number, since 2 + 1 + 57 + 2 + 52 + 552 + 0 = 666.

It is a super-2 number, since 2×21572525520² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21572525521) by changing a digit.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 501686619 + ... + 501686661.

It is an arithmetic number, because the mean of its divisors is an integer number (69225728).

Almost surely, 2^21572525520 is an apocalyptic number.

21572525520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21572525520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49842524160).

21572525520 is an abundant number, since it is smaller than the sum of its proper divisors (78112522800).

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

21572525520 is a wasteful number, since it uses less digits than its factorization.

21572525520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145 (or 123 counting only the distinct ones).

The product of its (nonzero) digits is 70000, while the sum is 36.

The spelling of 21572525520 in words is "twenty-one billion, five hundred seventy-two million, five hundred twenty-five thousand, five hundred twenty".