21036253804 has 6 divisors (see below), whose sum is σ = 36813444164. Its totient is φ = 10518126900.

The previous prime is 21036253793. The next prime is 21036253817. The reversal of 21036253804 is 40835263012.

It is a self number, because there is not a number n which added to its sum of digits gives 21036253804.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2629531722 + ... + 2629531729.

Almost surely, 2^21036253804 is an apocalyptic number.

It is an amenable number.

21036253804 is a deficient number, since it is larger than the sum of its proper divisors (15777190360).

21036253804 is a wasteful number, since it uses less digits than its factorization.

21036253804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5259063455 (or 5259063453 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 34.

The spelling of 21036253804 in words is "twenty-one billion, thirty-six million, two hundred fifty-three thousand, eight hundred four".