212201010021221 has 4 divisors (see below), whose sum is σ = 228524164638252. Its totient is φ = 195877855404192.

The previous prime is 212201010021173. The next prime is 212201010021229. The reversal of 212201010021221 is 122120010102212.

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 43250536392196 + 168950473629025 = 6576514^2 + 12998095^2 .

It is not a de Polignac number, because 212201010021221 - 2⁶ = 212201010021157 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 212201010021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212201010021229) 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, 8161577308496 + ... + 8161577308521.

It is an arithmetic number, because the mean of its divisors is an integer number (57131041159563).

Almost surely, 2^{212201010021221} is an apocalyptic number.

It is an amenable number.

212201010021221 is a deficient number, since it is larger than the sum of its proper divisors (16323154617031).

212201010021221 is a wasteful number, since it uses less digits than its factorization.

212201010021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16323154617030.

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

Adding to 212201010021221 its reverse (122120010102212), we get a palindrome (334321020123433).

The spelling of 212201010021221 in words is "two hundred twelve trillion, two hundred one billion, ten million, twenty-one thousand, two hundred twenty-one".