21221121104 has 20 divisors (see below), whose sum is σ = 41411724480. Its totient is φ = 10534224480.

The previous prime is 21221121067. The next prime is 21221121149. The reversal of 21221121104 is 40112112212.

It is a congruent number.

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, 4768712 + ... + 4773159.

It is an arithmetic number, because the mean of its divisors is an integer number (2070586224).

Almost surely, 2^21221121104 is an apocalyptic number.

It is an amenable number.

21221121104 is a deficient number, since it is larger than the sum of its proper divisors (20190603376).

21221121104 is a wasteful number, since it uses less digits than its factorization.

21221121104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9542018 (or 9542012 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21221121104 its reverse (40112112212), we get a palindrome (61333233316).

The spelling of 21221121104 in words is "twenty-one billion, two hundred twenty-one million, one hundred twenty-one thousand, one hundred four".