667940369 has 2 divisors, whose sum is σ = 667940370. Its totient is φ = 667940368.

The previous prime is 667940363. The next prime is 667940431. The reversal of 667940369 is 963049766.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 652036225 + 15904144 = 25535^2 + 3988^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-667940369 is a prime.

It is a super-2 number, since 2×667940369² = 892288673079712322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (667940363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333970184 + 333970185.

It is an arithmetic number, because the mean of its divisors is an integer number (333970185).

Almost surely, 2^667940369 is an apocalyptic number.

It is an amenable number.

667940369 is a deficient number, since it is larger than the sum of its proper divisors (1).

667940369 is an equidigital number, since it uses as much as digits as its factorization.

667940369 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1469664, while the sum is 50.

The square root of 667940369 is about 25844.5423445647. The cubic root of 667940369 is about 874.1364515438.

The spelling of 667940369 in words is "six hundred sixty-seven million, nine hundred forty thousand, three hundred sixty-nine".