77309865 has 24 divisors (see below), whose sum is σ = 134417088. Its totient is φ = 41104800.

The previous prime is 77309857. The next prime is 77309891. The reversal of 77309865 is 56890377.

It is a happy number.

It is not a de Polignac number, because 77309865 - 2³ = 77309857 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 77309865.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13140 + ... + 18090.

It is an arithmetic number, because the mean of its divisors is an integer number (5600712).

Almost surely, 2^77309865 is an apocalyptic number.

It is an amenable number.

77309865 is a deficient number, since it is larger than the sum of its proper divisors (57107223).

77309865 is a wasteful number, since it uses less digits than its factorization.

77309865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5309 (or 5306 counting only the distinct ones).

The product of its (nonzero) digits is 317520, while the sum is 45.

The square root of 77309865 is about 8792.6028569474. The cubic root of 77309865 is about 426.0020002551.

The spelling of 77309865 in words is "seventy-seven million, three hundred nine thousand, eight hundred sixty-five".