312289387 has 2 divisors, whose sum is σ = 312289388. Its totient is φ = 312289386.

The previous prime is 312289379. The next prime is 312289421. The reversal of 312289387 is 783982213.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 312289387 - 2³ = 312289379 is a prime.

It is a super-2 number, since 2×312289387² = 195049322465671538, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (312289357) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156144693 + 156144694.

It is an arithmetic number, because the mean of its divisors is an integer number (156144694).

Almost surely, 2^312289387 is an apocalyptic number.

312289387 is a deficient number, since it is larger than the sum of its proper divisors (1).

312289387 is an equidigital number, since it uses as much as digits as its factorization.

312289387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 43.

The square root of 312289387 is about 17671.7114904018. The cubic root of 312289387 is about 678.4519187838.

The spelling of 312289387 in words is "three hundred twelve million, two hundred eighty-nine thousand, three hundred eighty-seven".