20112212021021 has 4 divisors (see below), whose sum is σ = 20805736573500. Its totient is φ = 19418687468544.

The previous prime is 20112212021017. The next prime is 20112212021063. The reversal of 20112212021021 is 12012021221102.

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 12535069440100 + 7577142580921 = 3540490^2 + 2752661^2 .

It is a cyclic number.

It is not a de Polignac number, because 20112212021021 - 2² = 20112212021017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20112212021071) 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, 346762276196 + ... + 346762276253.

It is an arithmetic number, because the mean of its divisors is an integer number (5201434143375).

Almost surely, 2^{20112212021021} is an apocalyptic number.

It is an amenable number.

20112212021021 is a deficient number, since it is larger than the sum of its proper divisors (693524552479).

20112212021021 is an equidigital number, since it uses as much as digits as its factorization.

20112212021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 693524552478.

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

Adding to 20112212021021 its reverse (12012021221102), we get a palindrome (32124233242123).

The spelling of 20112212021021 in words is "twenty trillion, one hundred twelve billion, two hundred twelve million, twenty-one thousand, twenty-one".