664231423 has 2 divisors, whose sum is σ = 664231424. Its totient is φ = 664231422.

The previous prime is 664231417. The next prime is 664231441. The reversal of 664231423 is 324132466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 664231423 - 2²¹ = 662134271 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664231223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332115711 + 332115712.

It is an arithmetic number, because the mean of its divisors is an integer number (332115712).

Almost surely, 2^664231423 is an apocalyptic number.

664231423 is a deficient number, since it is larger than the sum of its proper divisors (1).

664231423 is an equidigital number, since it uses as much as digits as its factorization.

664231423 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 31.

The square root of 664231423 is about 25772.6875393312. The cubic root of 664231423 is about 872.5154762815.

Adding to 664231423 its reverse (324132466), we get a palindrome (988363889).

The spelling of 664231423 in words is "six hundred sixty-four million, two hundred thirty-one thousand, four hundred twenty-three".