21210023204 has 12 divisors (see below), whose sum is σ = 37124091228. Its totient is φ = 10603140000.

The previous prime is 21210023143. The next prime is 21210023251. The reversal of 21210023204 is 40232001212.

It can be written as a sum of positive squares in 2 ways, for example, as 9502350400 + 11707672804 = 97480^2 + 108202^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 442247 + ... + 487854.

It is an arithmetic number, because the mean of its divisors is an integer number (3093674269).

Almost surely, 2^21210023204 is an apocalyptic number.

It is an amenable number.

21210023204 is a deficient number, since it is larger than the sum of its proper divisors (15914068024).

21210023204 is a wasteful number, since it uses less digits than its factorization.

21210023204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 935806 (or 935804 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

Adding to 21210023204 its reverse (40232001212), we get a palindrome (61442024416).

The spelling of 21210023204 in words is "twenty-one billion, two hundred ten million, twenty-three thousand, two hundred four".