21613704256 has 189 divisors, whose sum is σ = 48662989669. Its totient is φ = 9521932288.

The previous prime is 21613704227. The next prime is 21613704271. The reversal of 21613704256 is 65240731612.

The square root of 21613704256 is 147016.

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., 16827278400 + 4786425856 = 129720^2 + 69184^2 .

It is a Duffinian number.

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, 459866025 + ... + 459866071.

Almost surely, 2^21613704256 is an apocalyptic number.

21613704256 is the 147016-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21613704256

21613704256 is an abundant number, since it is smaller than the sum of its proper divisors (27049285413).

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

21613704256 is an equidigital number, since it uses as much as digits as its factorization.

21613704256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186 (or 89 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 37.

The spelling of 21613704256 in words is "twenty-one billion, six hundred thirteen million, seven hundred four thousand, two hundred fifty-six".