21131524532550 has 48 divisors (see below), whose sum is σ = 52407294557760. Its totient is φ = 5634953454240.

The previous prime is 21131524532549. The next prime is 21131524532557. The reversal of 21131524532550 is 5523542513112.

It is a junction number, because it is equal to n+sod(n) for n = 21131524532499 and 21131524532508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21131524532557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5699829 + ... + 8645871.

It is an arithmetic number, because the mean of its divisors is an integer number (1091818636620).

Almost surely, 2^{21131524532550} is an apocalyptic number.

21131524532550 is an abundant number, since it is smaller than the sum of its proper divisors (31275770025210).

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

21131524532550 is a wasteful number, since it uses less digits than its factorization.

21131524532550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2993877 (or 2993872 counting only the distinct ones).

The product of its (nonzero) digits is 180000, while the sum is 39.

The spelling of 21131524532550 in words is "twenty-one trillion, one hundred thirty-one billion, five hundred twenty-four million, five hundred thirty-two thousand, five hundred fifty".