21147462621 has 24 divisors (see below), whose sum is σ = 31626181080. Its totient is φ = 13600734336.

The previous prime is 21147462587. The next prime is 21147462629. The reversal of 21147462621 is 12626474112.

21147462621 is a `hidden beast` number, since 2 + 1 + 1 + 4 + 7 + 4 + 626 + 21 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 31304025 + 21116158596 = 5595^2 + 145314^2 .

It is not a de Polignac number, because 21147462621 - 2¹⁰ = 21147461597 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21147462629) 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, 283195 + ... + 349991.

It is an arithmetic number, because the mean of its divisors is an integer number (1317757545).

Almost surely, 2^21147462621 is an apocalyptic number.

It is an amenable number.

21147462621 is a deficient number, since it is larger than the sum of its proper divisors (10478718459).

21147462621 is a wasteful number, since it uses less digits than its factorization.

21147462621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68045 (or 68042 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The spelling of 21147462621 in words is "twenty-one billion, one hundred forty-seven million, four hundred sixty-two thousand, six hundred twenty-one".