21516661314 has 40 divisors (see below), whose sum is σ = 48565231308. Its totient is φ = 7119861120.

The previous prime is 21516661301. The next prime is 21516661343. The reversal of 21516661314 is 41316661512.

It can be written as a sum of positive squares in 2 ways, for example, as 18237152025 + 3279509289 = 135045^2 + 57267^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 462547 + ... + 506934.

Almost surely, 2^21516661314 is an apocalyptic number.

21516661314 is an abundant number, since it is smaller than the sum of its proper divisors (27048569994).

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

21516661314 is a wasteful number, since it uses less digits than its factorization.

21516661314 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 969632 (or 969623 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The spelling of 21516661314 in words is "twenty-one billion, five hundred sixteen million, six hundred sixty-one thousand, three hundred fourteen".