211012212220021 has 4 divisors (see below), whose sum is σ = 211022868884044. Its totient is φ = 211001555556000.

The previous prime is 211012212219899. The next prime is 211012212220079. The reversal of 211012212220021 is 120022212210112.

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 1413887464900 + 209598324755121 = 1189070^2 + 14477511^2 .

It is a cyclic number.

It is not a de Polignac number, because 211012212220021 - 2⁹ = 211012212219509 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 (211012212227021) 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, 5328302310 + ... + 5328341911.

It is an arithmetic number, because the mean of its divisors is an integer number (52755717221011).

Almost surely, 2^{211012212220021} is an apocalyptic number.

It is an amenable number.

211012212220021 is a deficient number, since it is larger than the sum of its proper divisors (10656664023).

211012212220021 is a wasteful number, since it uses less digits than its factorization.

211012212220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10656664022.

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

Adding to 211012212220021 its reverse (120022212210112), we get a palindrome (331034424430133).

Subtracting from 211012212220021 its reverse (120022212210112), we obtain a palindrome (90990000009909).

The spelling of 211012212220021 in words is "two hundred eleven trillion, twelve billion, two hundred twelve million, two hundred twenty thousand, twenty-one".