21305522252 has 24 divisors (see below), whose sum is σ = 42614219424. Its totient is φ = 9130257792.

The previous prime is 21305522239. The next prime is 21305522261. The reversal of 21305522252 is 25222550312.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 593438 + ... + 628314.

It is an arithmetic number, because the mean of its divisors is an integer number (1775592476).

Almost surely, 2^21305522252 is an apocalyptic number.

It is an amenable number.

21305522252 is an abundant number, since it is smaller than the sum of its proper divisors (21308697172).

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

21305522252 is a wasteful number, since it uses less digits than its factorization.

21305522252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56705 (or 56703 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 29.

The spelling of 21305522252 in words is "twenty-one billion, three hundred five million, five hundred twenty-two thousand, two hundred fifty-two".