20122112120021 has 4 divisors (see below), whose sum is σ = 20122131340332. Its totient is φ = 20122092899712.

The previous prime is 20122112119979. The next prime is 20122112120053. The reversal of 20122112120021 is 12002121122102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2901023091121 + 17221089028900 = 1703239^2 + 4149830^2 .

It is a cyclic number.

It is not a de Polignac number, because 20122112120021 - 2¹⁸ = 20122111857877 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 (20122112123021) 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, 7943420 + ... + 10165733.

It is an arithmetic number, because the mean of its divisors is an integer number (5030532835083).

Almost surely, 2^{20122112120021} is an apocalyptic number.

It is an amenable number.

20122112120021 is a deficient number, since it is larger than the sum of its proper divisors (19220311).

20122112120021 is a wasteful number, since it uses less digits than its factorization.

20122112120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19220310.

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

Adding to 20122112120021 its reverse (12002121122102), we get a palindrome (32124233242123).

The spelling of 20122112120021 in words is "twenty trillion, one hundred twenty-two billion, one hundred twelve million, one hundred twenty thousand, twenty-one".