21017647458 has 24 divisors (see below), whose sum is σ = 46397450268. Its totient is φ = 6873695712.

The previous prime is 21017647439. The next prime is 21017647463. The reversal of 21017647458 is 85474671012.

21017647458 is a `hidden beast` number, since 2 + 1 + 0 + 176 + 474 + 5 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 20093913009 + 923734449 = 141753^2 + 30393^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11014585 + ... + 11016492.

Almost surely, 2^21017647458 is an apocalyptic number.

21017647458 is an abundant number, since it is smaller than the sum of its proper divisors (25379802810).

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

21017647458 is a wasteful number, since it uses less digits than its factorization.

21017647458 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22031138 (or 22031135 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 45.

The spelling of 21017647458 in words is "twenty-one billion, seventeen million, six hundred forty-seven thousand, four hundred fifty-eight".