78278305 has 16 divisors (see below), whose sum is σ = 108019584. Its totient is φ = 53343360.

The previous prime is 78278303. The next prime is 78278329. The reversal of 78278305 is 50387287.

It is not a de Polignac number, because 78278305 - 2¹ = 78278303 is a prime.

It is a super-2 number, since 2×78278305² = 12254986067346050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78278303) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1156 + ... + 12565.

It is an arithmetic number, because the mean of its divisors is an integer number (6751224).

Almost surely, 2^78278305 is an apocalyptic number.

It is an amenable number.

78278305 is a deficient number, since it is larger than the sum of its proper divisors (29741279).

78278305 is a wasteful number, since it uses less digits than its factorization.

78278305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13896.

The product of its (nonzero) digits is 94080, while the sum is 40.

The square root of 78278305 is about 8847.5027550151. The cubic root of 78278305 is about 427.7734283523.

The spelling of 78278305 in words is "seventy-eight million, two hundred seventy-eight thousand, three hundred five".