21021204336 has 80 divisors (see below), whose sum is σ = 59828277888. Its totient is φ = 6306976000.

The previous prime is 21021204311. The next prime is 21021204343. The reversal of 21021204336 is 63340212012.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

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 in 15 ways as a sum of consecutive naturals, for example, 143766 + ... + 250421.

Almost surely, 2^21021204336 is an apocalyptic number.

It is an amenable number.

21021204336 is an abundant number, since it is smaller than the sum of its proper divisors (38807073552).

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

21021204336 is a wasteful number, since it uses less digits than its factorization.

21021204336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394310 (or 394304 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 21021204336 its reverse (63340212012), we get a palindrome (84361416348).

The spelling of 21021204336 in words is "twenty-one billion, twenty-one million, two hundred four thousand, three hundred thirty-six".