666850069 has 2 divisors, whose sum is σ = 666850070. Its totient is φ = 666850068.

The previous prime is 666850043. The next prime is 666850073. The reversal of 666850069 is 960058666.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 341769169 + 325080900 = 18487^2 + 18030^2 .

It is a cyclic number.

It is not a de Polignac number, because 666850069 - 2²¹ = 664752917 is a prime.

It is a super-2 number, since 2×666850069² = 889378029050609522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666850169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333425034 + 333425035.

It is an arithmetic number, because the mean of its divisors is an integer number (333425035).

Almost surely, 2^666850069 is an apocalyptic number.

It is an amenable number.

666850069 is a deficient number, since it is larger than the sum of its proper divisors (1).

666850069 is an equidigital number, since it uses as much as digits as its factorization.

666850069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 466560, while the sum is 46.

The square root of 666850069 is about 25823.4403014006. The cubic root of 666850069 is about 873.6605657392.

The spelling of 666850069 in words is "six hundred sixty-six million, eight hundred fifty thousand, sixty-nine".