669421399 has 2 divisors, whose sum is σ = 669421400. Its totient is φ = 669421398.

The previous prime is 669421387. The next prime is 669421439. The reversal of 669421399 is 993124966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669421399 - 2⁵ = 669421367 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (669421339) 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, 334710699 + 334710700.

It is an arithmetic number, because the mean of its divisors is an integer number (334710700).

Almost surely, 2^669421399 is an apocalyptic number.

669421399 is a deficient number, since it is larger than the sum of its proper divisors (1).

669421399 is an equidigital number, since it uses as much as digits as its factorization.

669421399 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 629856, while the sum is 49.

The square root of 669421399 is about 25873.1791436615. The cubic root of 669421399 is about 874.7820514041.

The spelling of 669421399 in words is "six hundred sixty-nine million, four hundred twenty-one thousand, three hundred ninety-nine".