21705580612 has 12 divisors (see below), whose sum is σ = 37995252736. Its totient is φ = 10849794120.

The previous prime is 21705580609. The next prime is 21705580657. The reversal of 21705580612 is 21608550712.

It is a super-2 number, since 2×21705580612² (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, 732708 + ... + 761755.

Almost surely, 2^21705580612 is an apocalyptic number.

It is an amenable number.

21705580612 is a deficient number, since it is larger than the sum of its proper divisors (16289672124).

21705580612 is a wasteful number, since it uses less digits than its factorization.

21705580612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1498098 (or 1498096 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 37.

The spelling of 21705580612 in words is "twenty-one billion, seven hundred five million, five hundred eighty thousand, six hundred twelve".