669652391 has 2 divisors, whose sum is σ = 669652392. Its totient is φ = 669652390.

The previous prime is 669652387. The next prime is 669652469. The reversal of 669652391 is 193256966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669652391 - 2² = 669652387 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (669652691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334826195 + 334826196.

It is an arithmetic number, because the mean of its divisors is an integer number (334826196).

Almost surely, 2^669652391 is an apocalyptic number.

669652391 is a deficient number, since it is larger than the sum of its proper divisors (1).

669652391 is an equidigital number, since it uses as much as digits as its factorization.

669652391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 524880, while the sum is 47.

The square root of 669652391 is about 25877.6426863036. The cubic root of 669652391 is about 874.8826578972.

The spelling of 669652391 in words is "six hundred sixty-nine million, six hundred fifty-two thousand, three hundred ninety-one".