766665407 has 2 divisors, whose sum is σ = 766665408. Its totient is φ = 766665406.

The previous prime is 766665397. The next prime is 766665461. The reversal of 766665407 is 704566667.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 766665407 - 2⁴ = 766665391 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (766665007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 383332703 + 383332704.

It is an arithmetic number, because the mean of its divisors is an integer number (383332704).

Almost surely, 2^766665407 is an apocalyptic number.

766665407 is a deficient number, since it is larger than the sum of its proper divisors (1).

766665407 is an equidigital number, since it uses as much as digits as its factorization.

766665407 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1270080, while the sum is 47.

The square root of 766665407 is about 27688.7234628106. The cubic root of 766665407 is about 915.2406254985.

The spelling of 766665407 in words is "seven hundred sixty-six million, six hundred sixty-five thousand, four hundred seven".