666775132969 has 27 divisors (see below), whose sum is σ = 773703588861. Its totient is φ = 574109114040.

The previous prime is 666775132957. The next prime is 666775132981. The reversal of 666775132969 is 969231577666.

The square root of 666775132969 is 816563.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (666775132957) and next prime (666775132981).

It is not a de Polignac number, because 666775132969 - 2¹⁹ = 666774608681 is a prime.

It is a super-2 number, since 2×666775132969² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (666775132939) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 170659714 + ... + 170663620.

Almost surely, 2^666775132969 is an apocalyptic number.

666775132969 is the 816563-rd square number.

666775132969 is the 408282-nd centered octagonal number.

It is an amenable number.

666775132969 is a deficient number, since it is larger than the sum of its proper divisors (106928455892).

666775132969 is an frugal number, since it uses more digits than its factorization.

666775132969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7874 (or 3937 counting only the distinct ones).

The product of its digits is 154314720, while the sum is 67.

The spelling of 666775132969 in words is "six hundred sixty-six billion, seven hundred seventy-five million, one hundred thirty-two thousand, nine hundred sixty-nine".