78550865 has 16 divisors (see below), whose sum is σ = 100459008. Its totient is φ = 58825536.

The previous prime is 78550861. The next prime is 78550873. The reversal of 78550865 is 56805587.

It is not a de Polignac number, because 78550865 - 2² = 78550861 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 (78550861) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1862 + ... + 12671.

It is an arithmetic number, because the mean of its divisors is an integer number (6278688).

Almost surely, 2^78550865 is an apocalyptic number.

It is an amenable number.

78550865 is a deficient number, since it is larger than the sum of its proper divisors (21908143).

78550865 is a wasteful number, since it uses less digits than its factorization.

78550865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14608.

The product of its (nonzero) digits is 336000, while the sum is 44.

The square root of 78550865 is about 8862.8925865092. The cubic root of 78550865 is about 428.2693463576.

The spelling of 78550865 in words is "seventy-eight million, five hundred fifty thousand, eight hundred sixty-five".