666745031 has 2 divisors, whose sum is σ = 666745032. Its totient is φ = 666745030.

The previous prime is 666745021. The next prime is 666745109. The reversal of 666745031 is 130547666.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666745031 - 2¹⁰ = 666744007 is a prime.

It is a super-2 number, since 2×666745031² = 889097872726381922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666745021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333372515 + 333372516.

It is an arithmetic number, because the mean of its divisors is an integer number (333372516).

Almost surely, 2^666745031 is an apocalyptic number.

666745031 is a deficient number, since it is larger than the sum of its proper divisors (1).

666745031 is an equidigital number, since it uses as much as digits as its factorization.

666745031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90720, while the sum is 38.

The square root of 666745031 is about 25821.4064489137. The cubic root of 666745031 is about 873.6146921706.

The spelling of 666745031 in words is "six hundred sixty-six million, seven hundred forty-five thousand, thirty-one".