765990409 has 2 divisors, whose sum is σ = 765990410. Its totient is φ = 765990408.

The previous prime is 765990383. The next prime is 765990419. The reversal of 765990409 is 904099567.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 444577225 + 321413184 = 21085^2 + 17928^2 .

It is a cyclic number.

It is not a de Polignac number, because 765990409 - 2¹¹ = 765988361 is a prime.

It is not a weakly prime, because it can be changed into another prime (765990419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 382995204 + 382995205.

It is an arithmetic number, because the mean of its divisors is an integer number (382995205).

Almost surely, 2^765990409 is an apocalyptic number.

It is an amenable number.

765990409 is a deficient number, since it is larger than the sum of its proper divisors (1).

765990409 is an equidigital number, since it uses as much as digits as its factorization.

765990409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 612360, while the sum is 49.

The square root of 765990409 is about 27676.5317371957. The cubic root of 765990409 is about 914.9719437584.

The spelling of 765990409 in words is "seven hundred sixty-five million, nine hundred ninety thousand, four hundred nine".