21313203210 has 48 divisors (see below), whose sum is σ = 59676972264. Its totient is φ = 5246326656.

The previous prime is 21313203199. The next prime is 21313203217. The reversal of 21313203210 is 1230231312.

21313203210 is a `hidden beast` number, since 2 + 131 + 320 + 3 + 210 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 19010067129 + 2303136081 = 137877^2 + 47991^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21313203217) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9107037 + ... + 9109376.

Almost surely, 2^21313203210 is an apocalyptic number.

21313203210 is an abundant number, since it is smaller than the sum of its proper divisors (38363769054).

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

21313203210 is a wasteful number, since it uses less digits than its factorization.

21313203210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18216439 (or 18216436 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21313203210 its reverse (1230231312), we get a palindrome (22543434522).

The spelling of 21313203210 in words is "twenty-one billion, three hundred thirteen million, two hundred three thousand, two hundred ten".