21221002210 has 16 divisors (see below), whose sum is σ = 39858578496. Its totient is φ = 8119339888.

The previous prime is 21221002193. The next prime is 21221002217. The reversal of 21221002210 is 1220012212.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21221002217) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46132384 + ... + 46132843.

It is an arithmetic number, because the mean of its divisors is an integer number (2491161156).

Almost surely, 2^21221002210 is an apocalyptic number.

21221002210 is a deficient number, since it is larger than the sum of its proper divisors (18637576286).

21221002210 is a wasteful number, since it uses less digits than its factorization.

21221002210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92265257.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21221002210 its reverse (1220012212), we get a palindrome (22441014422).

The spelling of 21221002210 in words is "twenty-one billion, two hundred twenty-one million, two thousand, two hundred ten".