211212222200021 has 4 divisors (see below), whose sum is σ = 241385396800032. Its totient is φ = 181039047600012.

The previous prime is 211212222200009. The next prime is 211212222200069. The reversal of 211212222200021 is 120002222212112.

211212222200021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2^k-211212222200021 is a prime.

It is a super-2 number, since 2×211212222200021² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 211212222199966 and 211212222200002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211212222200071) 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, 15086587299995 + ... + 15086587300008.

It is an arithmetic number, because the mean of its divisors is an integer number (60346349200008).

Almost surely, 2^{211212222200021} is an apocalyptic number.

It is an amenable number.

211212222200021 is a deficient number, since it is larger than the sum of its proper divisors (30173174600011).

211212222200021 is an equidigital number, since it uses as much as digits as its factorization.

211212222200021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30173174600010.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 211212222200021 its reverse (120002222212112), we get a palindrome (331214444412133).

The spelling of 211212222200021 in words is "two hundred eleven trillion, two hundred twelve billion, two hundred twenty-two million, two hundred thousand, twenty-one".