665366431 has 2 divisors, whose sum is σ = 665366432. Its totient is φ = 665366430.

The previous prime is 665366407. The next prime is 665366437. The reversal of 665366431 is 134663566.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 665366431 - 2²¹ = 663269279 is a prime.

It is a super-2 number, since 2×665366431² = 885424975003355522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665366437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332683215 + 332683216.

It is an arithmetic number, because the mean of its divisors is an integer number (332683216).

Almost surely, 2^665366431 is an apocalyptic number.

665366431 is a deficient number, since it is larger than the sum of its proper divisors (1).

665366431 is an equidigital number, since it uses as much as digits as its factorization.

665366431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 233280, while the sum is 40.

The square root of 665366431 is about 25794.6977303476. The cubic root of 665366431 is about 873.0121648752.

The spelling of 665366431 in words is "six hundred sixty-five million, three hundred sixty-six thousand, four hundred thirty-one".