664967 has 2 divisors, whose sum is σ = 664968. Its totient is φ = 664966.

The previous prime is 664949. The next prime is 664973. The reversal of 664967 is 769466.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 664967 - 2⁸ = 664711 is a prime.

It is a super-2 number, since 2×664967² = 884362222178, which contains 22 as substring.

It is a Chen prime.

It is an Ulam number.

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 664967.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332483 + 332484.

It is an arithmetic number, because the mean of its divisors is an integer number (332484).

2⁶⁶⁴⁹⁶⁷ is an apocalyptic number.

664967 is a deficient number, since it is larger than the sum of its proper divisors (1).

664967 is an equidigital number, since it uses as much as digits as its factorization.

664967 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54432, while the sum is 38.

The square root of 664967 is about 815.4550876658. The cubic root of 664967 is about 87.2837435128.

The spelling of 664967 in words is "six hundred sixty-four thousand, nine hundred sixty-seven".