212021113121 has 4 divisors (see below), whose sum is σ = 212043967044. Its totient is φ = 211998259200.

The previous prime is 212021113079. The next prime is 212021113163. The reversal of 212021113121 is 121311120212.

It is a happy number.

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

It is an interprime number because it is at equal distance from previous prime (212021113079) and next prime (212021113163).

It can be written as a sum of positive squares in 2 ways, for example, as 140325160000 + 71695953121 = 374600^2 + 267761^2 .

It is a cyclic number.

It is not a de Polignac number, because 212021113121 - 2³⁴ = 194841243937 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 212021113121.

It is not an unprimeable number, because it can be changed into a prime (212021113021) 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, 11413040 + ... + 11431601.

It is an arithmetic number, because the mean of its divisors is an integer number (53010991761).

Almost surely, 2^212021113121 is an apocalyptic number.

It is an amenable number.

212021113121 is a deficient number, since it is larger than the sum of its proper divisors (22853923).

212021113121 is an equidigital number, since it uses as much as digits as its factorization.

212021113121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22853922.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 212021113121 its reverse (121311120212), we get a palindrome (333332233333).

The spelling of 212021113121 in words is "two hundred twelve billion, twenty-one million, one hundred thirteen thousand, one hundred twenty-one".