669191807 has 2 divisors, whose sum is σ = 669191808. Its totient is φ = 669191806.

The previous prime is 669191767. The next prime is 669191863. The reversal of 669191807 is 708191966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669191807 - 2¹⁸ = 668929663 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (669121807) 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, 334595903 + 334595904.

It is an arithmetic number, because the mean of its divisors is an integer number (334595904).

Almost surely, 2^669191807 is an apocalyptic number.

669191807 is a deficient number, since it is larger than the sum of its proper divisors (1).

669191807 is an equidigital number, since it uses as much as digits as its factorization.

669191807 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 163296, while the sum is 47.

The square root of 669191807 is about 25868.7418905520. The cubic root of 669191807 is about 874.6820317321.

The spelling of 669191807 in words is "six hundred sixty-nine million, one hundred ninety-one thousand, eight hundred seven".