312221344121221 has 4 divisors (see below), whose sum is σ = 312224729203692. Its totient is φ = 312217959038752.

The previous prime is 312221344121123. The next prime is 312221344121231. The reversal of 312221344121221 is 122121443122213.

It is a happy number.

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 185606863785121 + 126614480336100 = 13623761^2 + 11252310^2 .

It is a cyclic number.

It is not a de Polignac number, because 312221344121221 - 2⁹ = 312221344120709 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 (312221344121231) 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, 1692402880 + ... + 1692587353.

It is an arithmetic number, because the mean of its divisors is an integer number (78056182300923).

Almost surely, 2^{312221344121221} is an apocalyptic number.

It is an amenable number.

312221344121221 is a deficient number, since it is larger than the sum of its proper divisors (3385082471).

312221344121221 is an equidigital number, since it uses as much as digits as its factorization.

312221344121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3385082470.

The product of its digits is 9216, while the sum is 31.

Adding to 312221344121221 its reverse (122121443122213), we get a palindrome (434342787243434).

The spelling of 312221344121221 in words is "three hundred twelve trillion, two hundred twenty-one billion, three hundred forty-four million, one hundred twenty-one thousand, two hundred twenty-one".