21223251210 has 32 divisors (see below), whose sum is σ = 58212346752. Its totient is φ = 4851028800.

The previous prime is 21223251191. The next prime is 21223251241. The reversal of 21223251210 is 1215232212.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50531341 + ... + 50531760.

It is an arithmetic number, because the mean of its divisors is an integer number (1819135836).

Almost surely, 2^21223251210 is an apocalyptic number.

21223251210 is an abundant number, since it is smaller than the sum of its proper divisors (36989095542).

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

21223251210 is a wasteful number, since it uses less digits than its factorization.

21223251210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101063118.

The product of its (nonzero) digits is 480, while the sum is 21.

Adding to 21223251210 its reverse (1215232212), we get a palindrome (22438483422).

The spelling of 21223251210 in words is "twenty-one billion, two hundred twenty-three million, two hundred fifty-one thousand, two hundred ten".