311420381 has 2 divisors, whose sum is σ = 311420382. Its totient is φ = 311420380.

The previous prime is 311420359. The next prime is 311420407. The reversal of 311420381 is 183024113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 254115481 + 57304900 = 15941^2 + 7570^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-311420381 is a prime.

It is a super-2 number, since 2×311420381² = 193965307404370322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311420321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155710190 + 155710191.

It is an arithmetic number, because the mean of its divisors is an integer number (155710191).

Almost surely, 2^311420381 is an apocalyptic number.

It is an amenable number.

311420381 is a deficient number, since it is larger than the sum of its proper divisors (1).

311420381 is an equidigital number, since it uses as much as digits as its factorization.

311420381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 311420381 is about 17647.1068733660. The cubic root of 311420381 is about 677.8220259854.

Adding to 311420381 its reverse (183024113), we get a palindrome (494444494).

The spelling of 311420381 in words is "three hundred eleven million, four hundred twenty thousand, three hundred eighty-one".