21802884964 has 81 divisors (see below), whose sum is σ = 45466154937. Its totient is φ = 9121720608.

The previous prime is 21802884953. The next prime is 21802885021. The reversal of 21802884964 is 46948820812.

The square root of 21802884964 is 147658.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 15717636900 + 6085248064 = 125370^2 + 78008^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 109562137 + ... + 109562335.

Almost surely, 2^21802884964 is an apocalyptic number.

21802884964 is the 147658-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21802884964

21802884964 is an abundant number, since it is smaller than the sum of its proper divisors (23663269973).

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

21802884964 is an equidigital number, since it uses as much as digits as its factorization.

21802884964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 522 (or 261 counting only the distinct ones).

The product of its (nonzero) digits is 1769472, while the sum is 52.

The spelling of 21802884964 in words is "twenty-one billion, eight hundred two million, eight hundred eighty-four thousand, nine hundred sixty-four".