3111213321221 has 4 divisors (see below), whose sum is σ = 3112147903500. Its totient is φ = 3110278738944.

The previous prime is 3111213321197. The next prime is 3111213321239. The reversal of 3111213321221 is 1221233121113.

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 1146130830625 + 1965082490596 = 1070575^2 + 1401814^2 .

It is a cyclic number.

It is not a de Polignac number, because 3111213321221 - 2¹⁸ = 3111213059077 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 (3111213321421) 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, 467286146 + ... + 467292803.

It is an arithmetic number, because the mean of its divisors is an integer number (778036975875).

Almost surely, 2^{3111213321221} is an apocalyptic number.

It is an amenable number.

3111213321221 is a deficient number, since it is larger than the sum of its proper divisors (934582279).

3111213321221 is an equidigital number, since it uses as much as digits as its factorization.

3111213321221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 934582278.

The product of its digits is 432, while the sum is 23.

Adding to 3111213321221 its reverse (1221233121113), we get a palindrome (4332446442334).

The spelling of 3111213321221 in words is "three trillion, one hundred eleven billion, two hundred thirteen million, three hundred twenty-one thousand, two hundred twenty-one".