21521454524 has 24 divisors (see below), whose sum is σ = 37760175600. Its totient is φ = 10732861440.

The previous prime is 21521454517. The next prime is 21521454541. The reversal of 21521454524 is 42545412512.

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 7 ways as a sum of consecutive naturals, for example, 5472839 + ... + 5476769.

It is an arithmetic number, because the mean of its divisors is an integer number (1573340650).

Almost surely, 2^21521454524 is an apocalyptic number.

It is an amenable number.

21521454524 is a deficient number, since it is larger than the sum of its proper divisors (16238721076).

21521454524 is a wasteful number, since it uses less digits than its factorization.

21521454524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7133 (or 7131 counting only the distinct ones).

The product of its digits is 64000, while the sum is 35.

The spelling of 21521454524 in words is "twenty-one billion, five hundred twenty-one million, four hundred fifty-four thousand, five hundred twenty-four".