78665705 has 24 divisors (see below), whose sum is σ = 98860032. Its totient is φ = 60074784.

The previous prime is 78665701. The next prime is 78665707. The reversal of 78665705 is 50756687.

It is not a de Polignac number, because 78665705 - 2² = 78665701 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78665701) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 619352 + ... + 619478.

It is an arithmetic number, because the mean of its divisors is an integer number (4119168).

Almost surely, 2^78665705 is an apocalyptic number.

It is an amenable number.

78665705 is a deficient number, since it is larger than the sum of its proper divisors (20194327).

78665705 is a wasteful number, since it uses less digits than its factorization.

78665705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285 (or 242 counting only the distinct ones).

The product of its (nonzero) digits is 352800, while the sum is 44.

The square root of 78665705 is about 8869.3689177979. The cubic root of 78665705 is about 428.4779521793.

The spelling of 78665705 in words is "seventy-eight million, six hundred sixty-five thousand, seven hundred five".