78864155 has 32 divisors (see below), whose sum is σ = 104755200. Its totient is φ = 56764800.

The previous prime is 78864151. The next prime is 78864157. The reversal of 78864155 is 55146887.

It is a happy number.

It is not a de Polignac number, because 78864155 - 2² = 78864151 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78864151) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 179426 + ... + 179864.

It is an arithmetic number, because the mean of its divisors is an integer number (3273600).

Almost surely, 2^78864155 is an apocalyptic number.

78864155 is a deficient number, since it is larger than the sum of its proper divisors (25891045).

78864155 is a wasteful number, since it uses less digits than its factorization.

78864155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 555.

The product of its digits is 268800, while the sum is 44.

The square root of 78864155 is about 8880.5492510317. The cubic root of 78864155 is about 428.8379567781.

The spelling of 78864155 in words is "seventy-eight million, eight hundred sixty-four thousand, one hundred fifty-five".