664445983 has 2 divisors, whose sum is σ = 664445984. Its totient is φ = 664445982.

The previous prime is 664445939. The next prime is 664446043. The reversal of 664445983 is 389544466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 664445983 - 2¹³ = 664437791 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664445923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332222991 + 332222992.

It is an arithmetic number, because the mean of its divisors is an integer number (332222992).

Almost surely, 2^664445983 is an apocalyptic number.

664445983 is a deficient number, since it is larger than the sum of its proper divisors (1).

664445983 is an equidigital number, since it uses as much as digits as its factorization.

664445983 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2488320, while the sum is 49.

The square root of 664445983 is about 25776.8497493390. The cubic root of 664445983 is about 872.6094128025.

It can be divided in two parts, 66444 and 5983, that added together give a palindrome (72427).

The spelling of 664445983 in words is "six hundred sixty-four million, four hundred forty-five thousand, nine hundred eighty-three".