212220111100021 has 4 divisors (see below), whose sum is σ = 212220869333344. Its totient is φ = 212219352866700.

The previous prime is 212220111100007. The next prime is 212220111100027. The reversal of 212220111100021 is 120001111022212.

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 cyclic number.

It is not a de Polignac number, because 212220111100021 - 2⁵ = 212220111099989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212220111099968 and 212220111100004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212220111100027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 378696675 + ... + 379256656.

It is an arithmetic number, because the mean of its divisors is an integer number (53055217333336).

Almost surely, 2^{212220111100021} is an apocalyptic number.

It is an amenable number.

212220111100021 is a deficient number, since it is larger than the sum of its proper divisors (758233323).

212220111100021 is an equidigital number, since it uses as much as digits as its factorization.

212220111100021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 758233322.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 212220111100021 its reverse (120001111022212), we get a palindrome (332221222122233).

The spelling of 212220111100021 in words is "two hundred twelve trillion, two hundred twenty billion, one hundred eleven million, one hundred thousand, twenty-one".