765866641 has 4 divisors (see below), whose sum is σ = 766604800. Its totient is φ = 765128484.

The previous prime is 765866617. The next prime is 765866659. The reversal of 765866641 is 146668567.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 146668567 = 9479 ⋅15473.

It is a cyclic number.

It is not a de Polignac number, because 765866641 - 2⁷ = 765866513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (765866681) 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, 367521 + ... + 369598.

It is an arithmetic number, because the mean of its divisors is an integer number (191651200).

Almost surely, 2^765866641 is an apocalyptic number.

It is an amenable number.

765866641 is a deficient number, since it is larger than the sum of its proper divisors (738159).

765866641 is a wasteful number, since it uses less digits than its factorization.

765866641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 738158.

The product of its digits is 1451520, while the sum is 49.

The square root of 765866641 is about 27674.2956730609. The cubic root of 765866641 is about 914.9226610058.

The spelling of 765866641 in words is "seven hundred sixty-five million, eight hundred sixty-six thousand, six hundred forty-one".