311220137 has 2 divisors, whose sum is σ = 311220138. Its totient is φ = 311220136.

The previous prime is 311220127. The next prime is 311220157. The reversal of 311220137 is 731022113.

It is an a-pointer prime, because the next prime (311220157) can be obtained adding 311220137 to its sum of digits (20).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 268435456 + 42784681 = 16384^2 + 6541^2 .

It is a cyclic number.

It is not a de Polignac number, because 311220137 - 2⁴ = 311220121 is a prime.

It is not a weakly prime, because it can be changed into another prime (311220127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155610068 + 155610069.

It is an arithmetic number, because the mean of its divisors is an integer number (155610069).

Almost surely, 2^311220137 is an apocalyptic number.

It is an amenable number.

311220137 is a deficient number, since it is larger than the sum of its proper divisors (1).

311220137 is an equidigital number, since it uses as much as digits as its factorization.

311220137 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 252, while the sum is 20.

The square root of 311220137 is about 17641.4323964921. The cubic root of 311220137 is about 677.6767144772.

The spelling of 311220137 in words is "three hundred eleven million, two hundred twenty thousand, one hundred thirty-seven".