21503724536 has 16 divisors (see below), whose sum is σ = 46079409840. Its totient is φ = 9215881920.

The previous prime is 21503724533. The next prime is 21503724559. The reversal of 21503724536 is 63542730512.

It is a self number, because there is not a number n which added to its sum of digits gives 21503724536.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21503724533) 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 3 ways as a sum of consecutive naturals, for example, 191997485 + ... + 191997596.

It is an arithmetic number, because the mean of its divisors is an integer number (2879963115).

Almost surely, 2^21503724536 is an apocalyptic number.

It is an amenable number.

21503724536 is an abundant number, since it is smaller than the sum of its proper divisors (24575685304).

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

21503724536 is a wasteful number, since it uses less digits than its factorization.

21503724536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 383995094 (or 383995090 counting only the distinct ones).

The product of its (nonzero) digits is 151200, while the sum is 38.

The spelling of 21503724536 in words is "twenty-one billion, five hundred three million, seven hundred twenty-four thousand, five hundred thirty-six".