22121210120021 has 4 divisors (see below), whose sum is σ = 22148088869472. Its totient is φ = 22094331370572.

The previous prime is 22121210119993. The next prime is 22121210120063. The reversal of 22121210120021 is 12002101212122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 22121210120021 - 2²² = 22121205925717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22121210120081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13439373491 + ... + 13439375136.

It is an arithmetic number, because the mean of its divisors is an integer number (5537022217368).

Almost surely, 2^{22121210120021} is an apocalyptic number.

It is an amenable number.

22121210120021 is a deficient number, since it is larger than the sum of its proper divisors (26878749451).

22121210120021 is an equidigital number, since it uses as much as digits as its factorization.

22121210120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26878749450.

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

Adding to 22121210120021 its reverse (12002101212122), we get a palindrome (34123311332143).

It can be divided in two parts, 221212101 and 20021, that added together give a palindrome (221232122).

The spelling of 22121210120021 in words is "twenty-two trillion, one hundred twenty-one billion, two hundred ten million, one hundred twenty thousand, twenty-one".