311720399 has 4 divisors (see below), whose sum is σ = 311801400. Its totient is φ = 311639400.

The previous prime is 311720393. The next prime is 311720419. The reversal of 311720399 is 993027113.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 311720399 - 2¹² = 311716303 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311720393) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34424 + ... + 42525.

It is an arithmetic number, because the mean of its divisors is an integer number (77950350).

Almost surely, 2^311720399 is an apocalyptic number.

311720399 is a deficient number, since it is larger than the sum of its proper divisors (81001).

311720399 is an equidigital number, since it uses as much as digits as its factorization.

311720399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81000.

The product of its (nonzero) digits is 10206, while the sum is 35.

The square root of 311720399 is about 17655.6053138939. The cubic root of 311720399 is about 678.0396241813.

The spelling of 311720399 in words is "three hundred eleven million, seven hundred twenty thousand, three hundred ninety-nine".