666532397 has 2 divisors, whose sum is σ = 666532398. Its totient is φ = 666532396.

The previous prime is 666532343. The next prime is 666532403. The reversal of 666532397 is 793235666.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 595652836 + 70879561 = 24406^2 + 8419^2 .

It is a cyclic number.

It is not a de Polignac number, because 666532397 - 2¹² = 666528301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666534397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333266198 + 333266199.

It is an arithmetic number, because the mean of its divisors is an integer number (333266199).

Almost surely, 2^666532397 is an apocalyptic number.

It is an amenable number.

666532397 is a deficient number, since it is larger than the sum of its proper divisors (1).

666532397 is an equidigital number, since it uses as much as digits as its factorization.

666532397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1224720, while the sum is 47.

The square root of 666532397 is about 25817.2887228694. The cubic root of 666532397 is about 873.5218131197.

The spelling of 666532397 in words is "six hundred sixty-six million, five hundred thirty-two thousand, three hundred ninety-seven".