21221221010 has 16 divisors (see below), whose sum is σ = 41670761472. Its totient is φ = 7716807600.

The previous prime is 21221220997. The next prime is 21221221039. The reversal of 21221221010 is 1012212212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96459986 + ... + 96460205.

It is an arithmetic number, because the mean of its divisors is an integer number (2604422592).

Almost surely, 2^21221221010 is an apocalyptic number.

21221221010 is a deficient number, since it is larger than the sum of its proper divisors (20449540462).

21221221010 is a wasteful number, since it uses less digits than its factorization.

21221221010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192920209.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21221221010 its reverse (1012212212), we get a palindrome (22233433222).

The spelling of 21221221010 in words is "twenty-one billion, two hundred twenty-one million, two hundred twenty-one thousand, ten".