312197491 has 2 divisors, whose sum is σ = 312197492. Its totient is φ = 312197490.

The previous prime is 312197449. The next prime is 312197519. The reversal of 312197491 is 194791213.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 312197491 - 2²¹ = 310100339 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 312197491.

It is not a weakly prime, because it can be changed into another prime (312197891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156098745 + 156098746.

It is an arithmetic number, because the mean of its divisors is an integer number (156098746).

Almost surely, 2^312197491 is an apocalyptic number.

312197491 is a deficient number, since it is larger than the sum of its proper divisors (1).

312197491 is an equidigital number, since it uses as much as digits as its factorization.

312197491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13608, while the sum is 37.

The square root of 312197491 is about 17669.1112113768. Note that the first 3 decimals coincide. The cubic root of 312197491 is about 678.3853639188.

The spelling of 312197491 in words is "three hundred twelve million, one hundred ninety-seven thousand, four hundred ninety-one".