21561152426 has 32 divisors (see below), whose sum is σ = 36433483776. Its totient is φ = 9480870000.

The previous prime is 21561152401. The next prime is 21561152449. The reversal of 21561152426 is 62425116512.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2890001 + ... + 2897451.

It is an arithmetic number, because the mean of its divisors is an integer number (1138546368).

Almost surely, 2^21561152426 is an apocalyptic number.

21561152426 is a deficient number, since it is larger than the sum of its proper divisors (14872331350).

21561152426 is a wasteful number, since it uses less digits than its factorization.

21561152426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11738.

The product of its digits is 28800, while the sum is 35.

Adding to 21561152426 its reverse (62425116512), we get a palindrome (83986268938).

The spelling of 21561152426 in words is "twenty-one billion, five hundred sixty-one million, one hundred fifty-two thousand, four hundred twenty-six".