21525504531 has 8 divisors (see below), whose sum is σ = 28702104000. Its totient is φ = 14349620712.

The previous prime is 21525504521. The next prime is 21525504557. The reversal of 21525504531 is 13540552512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21525504531 - 2¹⁷ = 21525373459 is a prime.

It is a super-2 number, since 2×21525504531² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21525504492 and 21525504501.

It is not an unprimeable number, because it can be changed into a prime (21525504521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 104281 + ... + 232218.

It is an arithmetic number, because the mean of its divisors is an integer number (3587763000).

Almost surely, 2^21525504531 is an apocalyptic number.

21525504531 is a deficient number, since it is larger than the sum of its proper divisors (7176599469).

21525504531 is a wasteful number, since it uses less digits than its factorization.

21525504531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357825.

The product of its (nonzero) digits is 30000, while the sum is 33.

The spelling of 21525504531 in words is "twenty-one billion, five hundred twenty-five million, five hundred four thousand, five hundred thirty-one".