765641 has 4 divisors (see below), whose sum is σ = 786372. Its totient is φ = 744912.

The previous prime is 765623. The next prime is 765649. The reversal of 765641 is 146567.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 146567 = 97 ⋅1511.

It can be written as a sum of positive squares in 2 ways, for example, as 687241 + 78400 = 829^2 + 280^2 .

It is a cyclic number.

It is not a de Polignac number, because 765641 - 2⁶ = 765577 is a prime.

It is a super-2 number, since 2×765641² = 1172412281762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (765649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10310 + ... + 10383.

It is an arithmetic number, because the mean of its divisors is an integer number (196593).

2⁷⁶⁵⁶⁴¹ is an apocalyptic number.

It is an amenable number.

765641 is a deficient number, since it is larger than the sum of its proper divisors (20731).

765641 is a wasteful number, since it uses less digits than its factorization.

765641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20730.

The product of its digits is 5040, while the sum is 29.

The square root of 765641 is about 875.0091428094. The cubic root of 765641 is about 91.4832800130.

The spelling of 765641 in words is "seven hundred sixty-five thousand, six hundred forty-one".