21115351492 has 12 divisors (see below), whose sum is σ = 37332812860. Its totient is φ = 10448833536.

The previous prime is 21115351487. The next prime is 21115351513. The reversal of 21115351492 is 29415351112.

It can be written as a sum of positive squares in 2 ways, for example, as 6635079936 + 14480271556 = 81456^2 + 120334^2 .

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, 27210117 + ... + 27210892.

Almost surely, 2^21115351492 is an apocalyptic number.

It is an amenable number.

21115351492 is a deficient number, since it is larger than the sum of its proper divisors (16217461368).

21115351492 is a wasteful number, since it uses less digits than its factorization.

21115351492 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54421110 (or 54421108 counting only the distinct ones).

The product of its digits is 10800, while the sum is 34.

The spelling of 21115351492 in words is "twenty-one billion, one hundred fifteen million, three hundred fifty-one thousand, four hundred ninety-two".