78642867 has 16 divisors (see below), whose sum is σ = 114855840. Its totient is φ = 47642112.

The previous prime is 78642853. The next prime is 78642923. The reversal of 78642867 is 76824687.

It is a de Polignac number, because none of the positive numbers 2^k-78642867 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78642667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25108 + ... + 28065.

It is an arithmetic number, because the mean of its divisors is an integer number (7178490).

Almost surely, 2^78642867 is an apocalyptic number.

78642867 is a deficient number, since it is larger than the sum of its proper divisors (36212973).

78642867 is a wasteful number, since it uses less digits than its factorization.

78642867 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53222.

The product of its digits is 903168, while the sum is 48.

The square root of 78642867 is about 8868.0813595727. The cubic root of 78642867 is about 428.4364833394.

It can be divided in two parts, 7864 and 2867, that added together give a triangular number (10731 = T₁₄₆).

The spelling of 78642867 in words is "seventy-eight million, six hundred forty-two thousand, eight hundred sixty-seven".