21021827432 has 16 divisors (see below), whose sum is σ = 39488792100. Its totient is φ = 10491482880.

The previous prime is 21021827347. The next prime is 21021827441. The reversal of 21021827432 is 23472812012.

It can be written as a sum of positive squares in 2 ways, for example, as 20108941636 + 912885796 = 141806^2 + 30214^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2424257 + ... + 2432912.

Almost surely, 2^21021827432 is an apocalyptic number.

It is an amenable number.

21021827432 is a deficient number, since it is larger than the sum of its proper divisors (18466964668).

21021827432 is a wasteful number, since it uses less digits than its factorization.

21021827432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4857716 (or 4857712 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 32.

The spelling of 21021827432 in words is "twenty-one billion, twenty-one million, eight hundred twenty-seven thousand, four hundred thirty-two".