664943131 has 2 divisors, whose sum is σ = 664943132. Its totient is φ = 664943130.

The previous prime is 664943113. The next prime is 664943137. The reversal of 664943131 is 131349466.

664943131 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with previous prime (664943113) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 664943131 - 2¹¹ = 664941083 is a prime.

It is a super-2 number, since 2×664943131² = 884298734928166322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (664943137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332471565 + 332471566.

It is an arithmetic number, because the mean of its divisors is an integer number (332471566).

Almost surely, 2^664943131 is an apocalyptic number.

664943131 is a deficient number, since it is larger than the sum of its proper divisors (1).

664943131 is an equidigital number, since it uses as much as digits as its factorization.

664943131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 37.

The square root of 664943131 is about 25786.4912502651. The cubic root of 664943131 is about 872.8269914994.

The spelling of 664943131 in words is "six hundred sixty-four million, nine hundred forty-three thousand, one hundred thirty-one".