21455515140232 has 32 divisors (see below), whose sum is σ = 42598919832120. Its totient is φ = 10095904276480.

The previous prime is 21455515140229. The next prime is 21455515140253. The reversal of 21455515140232 is 23204151555412.

It can be written as a sum of positive squares in 4 ways, for example, as 21289789615396 + 165725524836 = 4614086^2 + 407094^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4612369 + ... + 8011552.

Almost surely, 2^{21455515140232} is an apocalyptic number.

It is an amenable number.

21455515140232 is a deficient number, since it is larger than the sum of its proper divisors (21143404691888).

21455515140232 is a wasteful number, since it uses less digits than its factorization.

21455515140232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12636441 (or 12636437 counting only the distinct ones).

The product of its (nonzero) digits is 240000, while the sum is 40.

Adding to 21455515140232 its reverse (23204151555412), we get a palindrome (44659666695644).

The spelling of 21455515140232 in words is "twenty-one trillion, four hundred fifty-five billion, five hundred fifteen million, one hundred forty thousand, two hundred thirty-two".