21131788492 has 6 divisors (see below), whose sum is σ = 36980629868. Its totient is φ = 10565894244.

The previous prime is 21131788439. The next prime is 21131788501. The reversal of 21131788492 is 29488713112.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2641473558 + ... + 2641473565.

Almost surely, 2^21131788492 is an apocalyptic number.

It is an amenable number.

21131788492 is a deficient number, since it is larger than the sum of its proper divisors (15848841376).

21131788492 is a wasteful number, since it uses less digits than its factorization.

21131788492 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5282947127 (or 5282947125 counting only the distinct ones).

The product of its digits is 193536, while the sum is 46.

The spelling of 21131788492 in words is "twenty-one billion, one hundred thirty-one million, seven hundred eighty-eight thousand, four hundred ninety-two".