21001512532 has 48 divisors (see below), whose sum is σ = 49346220672. Its totient is φ = 7552990080.

The previous prime is 21001512529. The next prime is 21001512541. The reversal of 21001512532 is 23521510012.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 2618563 + ... + 2626570.

It is an arithmetic number, because the mean of its divisors is an integer number (1028046264).

Almost surely, 2^21001512532 is an apocalyptic number.

21001512532 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21001512532 is an abundant number, since it is smaller than the sum of its proper divisors (28344708140).

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

21001512532 is a wasteful number, since it uses less digits than its factorization.

21001512532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5245168 (or 5245166 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 22.

The spelling of 21001512532 in words is "twenty-one billion, one million, five hundred twelve thousand, five hundred thirty-two".