21440415204 has 60 divisors (see below), whose sum is σ = 60360990844. Its totient is φ = 6597049536.

The previous prime is 21440415187. The next prime is 21440415211. The reversal of 21440415204 is 40251404412.

21440415204 is a `hidden beast` number, since 2 + 1 + 4 + 40 + 415 + 204 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 13959895104 + 7480520100 = 118152^2 + 86490^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

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, 2540947 + ... + 2549370.

Almost surely, 2^21440415204 is an apocalyptic number.

It is an amenable number.

21440415204 is an abundant number, since it is smaller than the sum of its proper divisors (38920575640).

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

21440415204 is a wasteful number, since it uses less digits than its factorization.

21440415204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5090346 (or 5090335 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 27.

Adding to 21440415204 its reverse (40251404412), we get a palindrome (61691819616).

The spelling of 21440415204 in words is "twenty-one billion, four hundred forty million, four hundred fifteen thousand, two hundred four".