21315634554 has 8 divisors (see below), whose sum is σ = 42631269120. Its totient is φ = 7105211516.

The previous prime is 21315634553. The next prime is 21315634567. The reversal of 21315634554 is 45543651312.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

21315634554 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21315634553) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1776302874 + ... + 1776302885.

It is an arithmetic number, because the mean of its divisors is an integer number (5328908640).

Almost surely, 2^21315634554 is an apocalyptic number.

21315634554 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21315634554 is a wasteful number, since it uses less digits than its factorization.

21315634554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3552605764.

The product of its digits is 216000, while the sum is 39.

The spelling of 21315634554 in words is "twenty-one billion, three hundred fifteen million, six hundred thirty-four thousand, five hundred fifty-four".