21802591552 has 42 divisors (see below), whose sum is σ = 50328119562. Its totient is φ = 9343966464.

The previous prime is 21802591537. The next prime is 21802591553. The reversal of 21802591552 is 25519520812.

It can be written as a sum of positive squares in only one way, i.e., 20057357376 + 1745234176 = 141624^2 + 41776^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21802591553) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3473043 + ... + 3479314.

It is an arithmetic number, because the mean of its divisors is an integer number (1198288561).

Almost surely, 2^21802591552 is an apocalyptic number.

It is an amenable number.

21802591552 is an abundant number, since it is smaller than the sum of its proper divisors (28525528010).

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

21802591552 is an equidigital number, since it uses as much as digits as its factorization.

21802591552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6952383 (or 6952366 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 40.

The spelling of 21802591552 in words is "twenty-one billion, eight hundred two million, five hundred ninety-one thousand, five hundred fifty-two".