666032981 has 2 divisors, whose sum is σ = 666032982. Its totient is φ = 666032980.

The previous prime is 666032959. The next prime is 666033029. The reversal of 666032981 is 189230666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 663886756 + 2146225 = 25766^2 + 1465^2 .

It is a cyclic number.

It is not a de Polignac number, because 666032981 - 2¹⁸ = 665770837 is a prime.

It is a super-2 number, since 2×666032981² = 887199863559492722, which contains 22 as substring.

It is equal to p_34583297 and since 666032981 and 34583297 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666032581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333016490 + 333016491.

It is an arithmetic number, because the mean of its divisors is an integer number (333016491).

Almost surely, 2^666032981 is an apocalyptic number.

It is an amenable number.

666032981 is a deficient number, since it is larger than the sum of its proper divisors (1).

666032981 is an equidigital number, since it uses as much as digits as its factorization.

666032981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 93312, while the sum is 41.

The square root of 666032981 is about 25807.6147871127. The cubic root of 666032981 is about 873.3035892822.

The spelling of 666032981 in words is "six hundred sixty-six million, thirty-two thousand, nine hundred eighty-one".