321309137 has 2 divisors, whose sum is σ = 321309138. Its totient is φ = 321309136.

The previous prime is 321309089. The next prime is 321309139. The reversal of 321309137 is 731903123.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 287946961 + 33362176 = 16969^2 + 5776^2 .

It is a cyclic number.

It is not a de Polignac number, because 321309137 - 2²⁶ = 254200273 is a prime.

Together with 321309139, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (321309139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160654568 + 160654569.

It is an arithmetic number, because the mean of its divisors is an integer number (160654569).

Almost surely, 2^321309137 is an apocalyptic number.

It is an amenable number.

321309137 is a deficient number, since it is larger than the sum of its proper divisors (1).

321309137 is an equidigital number, since it uses as much as digits as its factorization.

321309137 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3402, while the sum is 29.

The square root of 321309137 is about 17925.0979634701. The cubic root of 321309137 is about 684.9218565733.

The spelling of 321309137 in words is "three hundred twenty-one million, three hundred nine thousand, one hundred thirty-seven".