21583565952 has 192 divisors, whose sum is σ = 62702827200. Its totient is φ = 6574583808.

The previous prime is 21583565947. The next prime is 21583565963. The reversal of 21583565952 is 25956538512.

It is a tau number, because it is divible by the number of its divisors (192).

Its product of digits (3240000) is a multiple of the sum of its prime factors (3375).

It is a junction number, because it is equal to n+sod(n) for n = 21583565895 and 21583565904.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6682674 + ... + 6685902.

It is an arithmetic number, because the mean of its divisors is an integer number (326577225).

Almost surely, 2^21583565952 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21583565952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31351413600).

21583565952 is an abundant number, since it is smaller than the sum of its proper divisors (41119261248).

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

21583565952 is a wasteful number, since it uses less digits than its factorization.

21583565952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3375 (or 3350 counting only the distinct ones).

The product of its digits is 3240000, while the sum is 51.

The spelling of 21583565952 in words is "twenty-one billion, five hundred eighty-three million, five hundred sixty-five thousand, nine hundred fifty-two".