21517225074 has 60 divisors (see below), whose sum is σ = 51217614954. Its totient is φ = 6750487296.

The previous prime is 21517225049. The next prime is 21517225141. The reversal of 21517225074 is 47052271512.

21517225074 is a `hidden beast` number, since 2 + 1 + 517 + 22 + 50 + 74 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 21454925625 + 62299449 = 146475^2 + 7893^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 182979 + ... + 276614.

Almost surely, 2^21517225074 is an apocalyptic number.

21517225074 is an abundant number, since it is smaller than the sum of its proper divisors (29700389880).

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

21517225074 is a wasteful number, since it uses less digits than its factorization.

21517225074 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 459641 (or 459615 counting only the distinct ones).

The product of its (nonzero) digits is 39200, while the sum is 36.

Adding to 21517225074 its reverse (47052271512), we get a palindrome (68569496586).

The spelling of 21517225074 in words is "twenty-one billion, five hundred seventeen million, two hundred twenty-five thousand, seventy-four".