668429423 has 2 divisors, whose sum is σ = 668429424. Its totient is φ = 668429422.

The previous prime is 668429417. The next prime is 668429431. The reversal of 668429423 is 324924866.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 668429423 - 2⁴ = 668429407 is a prime.

It is a super-2 number, since 2×668429423² = 893595787064225858, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (668429483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334214711 + 334214712.

It is an arithmetic number, because the mean of its divisors is an integer number (334214712).

Almost surely, 2^668429423 is an apocalyptic number.

668429423 is a deficient number, since it is larger than the sum of its proper divisors (1).

668429423 is an equidigital number, since it uses as much as digits as its factorization.

668429423 is an evil number, because the sum of its binary digits is even.

The product of its digits is 497664, while the sum is 44.

The square root of 668429423 is about 25854.0020693122. The cubic root of 668429423 is about 874.3497418586.

The spelling of 668429423 in words is "six hundred sixty-eight million, four hundred twenty-nine thousand, four hundred twenty-three".