21612640773572 has 12 divisors (see below), whose sum is σ = 38442156130476. Its totient is φ = 10629167593440.

The previous prime is 21612640773571. The next prime is 21612640773583. The reversal of 21612640773572 is 27537704621612.

It can be written as a sum of positive squares in 2 ways, for example, as 6213483494596 + 15399157278976 = 2492686^2 + 3924176^2 .

It is not an unprimeable number, because it can be changed into a prime (21612640773571) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44288198063 + ... + 44288198550.

It is an arithmetic number, because the mean of its divisors is an integer number (3203513010873).

Almost surely, 2^{21612640773572} is an apocalyptic number.

It is an amenable number.

21612640773572 is a deficient number, since it is larger than the sum of its proper divisors (16829515356904).

21612640773572 is a wasteful number, since it uses less digits than its factorization.

21612640773572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88576396678 (or 88576396676 counting only the distinct ones).

The product of its (nonzero) digits is 5927040, while the sum is 53.

The spelling of 21612640773572 in words is "twenty-one trillion, six hundred twelve billion, six hundred forty million, seven hundred seventy-three thousand, five hundred seventy-two".