311451997 has 2 divisors, whose sum is σ = 311451998. Its totient is φ = 311451996.

The previous prime is 311451991. The next prime is 311452007. The reversal of 311451997 is 799154113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 288354361 + 23097636 = 16981^2 + 4806^2 .

It is a cyclic number.

It is not a de Polignac number, because 311451997 - 2³ = 311451989 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311451991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155725998 + 155725999.

It is an arithmetic number, because the mean of its divisors is an integer number (155725999).

Almost surely, 2^311451997 is an apocalyptic number.

It is an amenable number.

311451997 is a deficient number, since it is larger than the sum of its proper divisors (1).

311451997 is an equidigital number, since it uses as much as digits as its factorization.

311451997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34020, while the sum is 40.

The square root of 311451997 is about 17648.0026348593. The cubic root of 311451997 is about 677.8449631440.

The spelling of 311451997 in words is "three hundred eleven million, four hundred fifty-one thousand, nine hundred ninety-seven".