21000601516 has 12 divisors (see below), whose sum is σ = 37353529360. Its totient is φ = 10328164560.

The previous prime is 21000601511. The next prime is 21000601537. The reversal of 21000601516 is 61510600012.

It is not an unprimeable number, because it can be changed into a prime (21000601511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43033776 + ... + 43034263.

Almost surely, 2^21000601516 is an apocalyptic number.

It is an amenable number.

21000601516 is a deficient number, since it is larger than the sum of its proper divisors (16352927844).

21000601516 is a wasteful number, since it uses less digits than its factorization.

21000601516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86068104 (or 86068102 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 22.

The spelling of 21000601516 in words is "twenty-one billion, six hundred one thousand, five hundred sixteen".