765436381 has 2 divisors, whose sum is σ = 765436382. Its totient is φ = 765436380.

The previous prime is 765436379. The next prime is 765436403. The reversal of 765436381 is 183634567.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 760104900 + 5331481 = 27570^2 + 2309^2 .

It is an emirp because it is prime and its reverse (183634567) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 765436381 - 2¹ = 765436379 is a prime.

It is a super-2 number, since 2×765436381² = 1171785706716754322, which contains 22 as substring.

Together with 765436379, it forms a pair of twin primes.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (765436351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 382718190 + 382718191.

It is an arithmetic number, because the mean of its divisors is an integer number (382718191).

Almost surely, 2^765436381 is an apocalyptic number.

It is an amenable number.

765436381 is a deficient number, since it is larger than the sum of its proper divisors (1).

765436381 is an equidigital number, since it uses as much as digits as its factorization.

765436381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 362880, while the sum is 43.

The square root of 765436381 is about 27666.5209413833. The cubic root of 765436381 is about 914.7512959387.

The spelling of 765436381 in words is "seven hundred sixty-five million, four hundred thirty-six thousand, three hundred eighty-one".