666450331 has 2 divisors, whose sum is σ = 666450332. Its totient is φ = 666450330.

The previous prime is 666450319. The next prime is 666450341. The reversal of 666450331 is 133054666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 666450331 - 2¹¹ = 666448283 is a prime.

It is a super-2 number, since 2×666450331² = 888312087380019122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (666450311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333225165 + 333225166.

It is an arithmetic number, because the mean of its divisors is an integer number (333225166).

Almost surely, 2^666450331 is an apocalyptic number.

666450331 is a deficient number, since it is larger than the sum of its proper divisors (1).

666450331 is an equidigital number, since it uses as much as digits as its factorization.

666450331 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 34.

The square root of 666450331 is about 25815.6993126276. The cubic root of 666450331 is about 873.4859612072.

The spelling of 666450331 in words is "six hundred sixty-six million, four hundred fifty thousand, three hundred thirty-one".