21452904265984 has 81 divisors (see below), whose sum is σ = 42999511025457. Its totient is φ = 10682172813312.

The previous prime is 21452904265913. The next prime is 21452904265987. The reversal of 21452904265984 is 48956240925412.

The square root of 21452904265984 is 4631728.

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., 5784987040000 + 15667917225984 = 2405200^2 + 3958272^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21452904265987) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 24974276947 + ... + 24974277805.

Almost surely, 2^{21452904265984} is an apocalyptic number.

21452904265984 is the 4631728-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21452904265984

21452904265984 is an abundant number, since it is smaller than the sum of its proper divisors (21546606759473).

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

21452904265984 is an frugal number, since it uses more digits than its factorization.

21452904265984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2408 (or 1198 counting only the distinct ones).

The product of its (nonzero) digits is 49766400, while the sum is 61.

The spelling of 21452904265984 in words is "twenty-one trillion, four hundred fifty-two billion, nine hundred four million, two hundred sixty-five thousand, nine hundred eighty-four".