202102212112021 has 4 divisors (see below), whose sum is σ = 217648536120652. Its totient is φ = 186555888103392.

The previous prime is 202102212111923. The next prime is 202102212112067. The reversal of 202102212112021 is 120211212201202.

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 68964537551121 + 133137674560900 = 8304489^2 + 11538530^2 .

It is a cyclic number.

It is not a de Polignac number, because 202102212112021 - 2²¹ = 202102210014869 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 202102212112021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (202102212112621) 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, 7773162004296 + ... + 7773162004321.

It is an arithmetic number, because the mean of its divisors is an integer number (54412134030163).

Almost surely, 2^{202102212112021} is an apocalyptic number.

It is an amenable number.

202102212112021 is a deficient number, since it is larger than the sum of its proper divisors (15546324008631).

202102212112021 is a wasteful number, since it uses less digits than its factorization.

202102212112021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15546324008630.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 202102212112021 its reverse (120211212201202), we get a palindrome (322313424313223).

The spelling of 202102212112021 in words is "two hundred two trillion, one hundred two billion, two hundred twelve million, one hundred twelve thousand, twenty-one".