78157278 has 32 divisors (see below), whose sum is σ = 174182400. Its totient is φ = 25977528.

The previous prime is 78157249. The next prime is 78157319. The reversal of 78157278 is 87275187.

78157278 is a `hidden beast` number, since 7 + 8 + 1 + 572 + 78 = 666.

It is a super-2 number, since 2×78157278² = 12217120208738568, which contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18793 + ... + 22571.

It is an arithmetic number, because the mean of its divisors is an integer number (5443200).

Almost surely, 2^78157278 is an apocalyptic number.

78157278 is an abundant number, since it is smaller than the sum of its proper divisors (96025122).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78157278 is a wasteful number, since it uses less digits than its factorization.

78157278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4173 (or 4167 counting only the distinct ones).

The product of its digits is 219520, while the sum is 45.

The square root of 78157278 is about 8840.6604956870. The cubic root of 78157278 is about 427.5528528068.

The spelling of 78157278 in words is "seventy-eight million, one hundred fifty-seven thousand, two hundred seventy-eight".