21000131451 has 24 divisors (see below), whose sum is σ = 32711937440. Its totient is φ = 12905329536.

The previous prime is 21000131419. The next prime is 21000131461. The reversal of 21000131451 is 15413100012.

21000131451 is a `hidden beast` number, since 210 + 0 + 0 + 1 + 3 + 1 + 451 = 666.

It is not a de Polignac number, because 21000131451 - 2⁵ = 21000131419 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21000131461) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38386 + ... + 208503.

Almost surely, 2^21000131451 is an apocalyptic number.

21000131451 is a deficient number, since it is larger than the sum of its proper divisors (11711805989).

21000131451 is a wasteful number, since it uses less digits than its factorization.

21000131451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247635 (or 247632 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

Adding to 21000131451 its reverse (15413100012), we get a palindrome (36413231463).

The spelling of 21000131451 in words is "twenty-one billion, one hundred thirty-one thousand, four hundred fifty-one".