21489879512 has 32 divisors (see below), whose sum is σ = 41738360400. Its totient is φ = 10360635264.

The previous prime is 21489879511. The next prime is 21489879553. The reversal of 21489879512 is 21597898412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21489879511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 114443 + ... + 236805.

Almost surely, 2^21489879512 is an apocalyptic number.

It is an amenable number.

21489879512 is a deficient number, since it is larger than the sum of its proper divisors (20248480888).

21489879512 is a wasteful number, since it uses less digits than its factorization.

21489879512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123155 (or 123151 counting only the distinct ones).

The product of its digits is 2903040, while the sum is 56.

The spelling of 21489879512 in words is "twenty-one billion, four hundred eighty-nine million, eight hundred seventy-nine thousand, five hundred twelve".