21017742572 has 12 divisors (see below), whose sum is σ = 37070664960. Its totient is φ = 10426124016.

The previous prime is 21017742521. The next prime is 21017742619. The reversal of 21017742572 is 27524771012.

It is a super-2 number, since 2×21017742572² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20686247 + ... + 20687262.

It is an arithmetic number, because the mean of its divisors is an integer number (3089222080).

Almost surely, 2^21017742572 is an apocalyptic number.

It is an amenable number.

21017742572 is a deficient number, since it is larger than the sum of its proper divisors (16052922388).

21017742572 is a wasteful number, since it uses less digits than its factorization.

21017742572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41373640 (or 41373638 counting only the distinct ones).

The product of its (nonzero) digits is 54880, while the sum is 38.

The spelling of 21017742572 in words is "twenty-one billion, seventeen million, seven hundred forty-two thousand, five hundred seventy-two".