3122331721 has 2 divisors, whose sum is σ = 3122331722. Its totient is φ = 3122331720.

The previous prime is 3122331701. The next prime is 3122331761. The reversal of 3122331721 is 1271332213.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1923787321 + 1198544400 = 43861^2 + 34620^2 .

It is a cyclic number.

It is not a de Polignac number, because 3122331721 - 2¹¹ = 3122329673 is a prime.

It is not a weakly prime, because it can be changed into another prime (3122331701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1561165860 + 1561165861.

It is an arithmetic number, because the mean of its divisors is an integer number (1561165861).

Almost surely, 2^3122331721 is an apocalyptic number.

It is an amenable number.

3122331721 is a deficient number, since it is larger than the sum of its proper divisors (1).

3122331721 is an equidigital number, since it uses as much as digits as its factorization.

3122331721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1512, while the sum is 25.

The square root of 3122331721 is about 55877.8285279591. The cubic root of 3122331721 is about 1461.5926388779.

Adding to 3122331721 its reverse (1271332213), we get a palindrome (4393663934).

The spelling of 3122331721 in words is "three billion, one hundred twenty-two million, three hundred thirty-one thousand, seven hundred twenty-one".