78865790 has 32 divisors (see below), whose sum is σ = 147908160. Its totient is φ = 30240000.

The previous prime is 78865777. The next prime is 78865793. The reversal of 78865790 is 9756887.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78865793) 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, 42890 + ... + 44690.

It is an arithmetic number, because the mean of its divisors is an integer number (4622130).

Almost surely, 2^78865790 is an apocalyptic number.

78865790 is a deficient number, since it is larger than the sum of its proper divisors (69042370).

78865790 is a wasteful number, since it uses less digits than its factorization.

78865790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1988.

The product of its (nonzero) digits is 846720, while the sum is 50.

The square root of 78865790 is about 8880.6413056716. The cubic root of 78865790 is about 428.8409202927.

The spelling of 78865790 in words is "seventy-eight million, eight hundred sixty-five thousand, seven hundred ninety".