21204031304 has 16 divisors (see below), whose sum is σ = 40151199420. Its totient is φ = 10497044800.

The previous prime is 21204031291. The next prime is 21204031307. The reversal of 21204031304 is 40313040212.

It can be written as a sum of positive squares in 2 ways, for example, as 14691864100 + 6512167204 = 121210^2 + 80698^2 .

It is a super-2 number, since 2×21204031304² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21204031307) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13120499 + ... + 13122114.

Almost surely, 2^21204031304 is an apocalyptic number.

It is an amenable number.

21204031304 is a deficient number, since it is larger than the sum of its proper divisors (18947168116).

21204031304 is a wasteful number, since it uses less digits than its factorization.

21204031304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26242720 (or 26242716 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21204031304 its reverse (40313040212), we get a palindrome (61517071516).

The spelling of 21204031304 in words is "twenty-one billion, two hundred four million, thirty-one thousand, three hundred four".