78646155 has 16 divisors (see below), whose sum is σ = 143810304. Its totient is φ = 35952480.

The previous prime is 78646151. The next prime is 78646171. The reversal of 78646155 is 55164687.

It is not a de Polignac number, because 78646155 - 2² = 78646151 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78646151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 374401 + ... + 374610.

It is an arithmetic number, because the mean of its divisors is an integer number (8988144).

Almost surely, 2^78646155 is an apocalyptic number.

78646155 is a deficient number, since it is larger than the sum of its proper divisors (65164149).

78646155 is a wasteful number, since it uses less digits than its factorization.

78646155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 749026.

The product of its digits is 201600, while the sum is 42.

The square root of 78646155 is about 8868.2667415905. The cubic root of 78646155 is about 428.4424541268.

The spelling of 78646155 in words is "seventy-eight million, six hundred forty-six thousand, one hundred fifty-five".