311781641 has 2 divisors, whose sum is σ = 311781642. Its totient is φ = 311781640.

The previous prime is 311781599. The next prime is 311781653. The reversal of 311781641 is 146187113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 310781641 + 1000000 = 17629^2 + 1000^2 .

It is a cyclic number.

It is not a de Polignac number, because 311781641 - 2¹⁴ = 311765257 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 311781598 and 311781607.

It is not a weakly prime, because it can be changed into another prime (311781341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155890820 + 155890821.

It is an arithmetic number, because the mean of its divisors is an integer number (155890821).

Almost surely, 2^311781641 is an apocalyptic number.

It is an amenable number.

311781641 is a deficient number, since it is larger than the sum of its proper divisors (1).

311781641 is an equidigital number, since it uses as much as digits as its factorization.

311781641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4032, while the sum is 32.

The square root of 311781641 is about 17657.3395787701. The cubic root of 311781641 is about 678.0840248511.

The spelling of 311781641 in words is "three hundred eleven million, seven hundred eighty-one thousand, six hundred forty-one".