78057778 has 8 divisors (see below), whose sum is σ = 123974172. Its totient is φ = 36733056.

The previous prime is 78057751. The next prime is 78057781. The reversal of 78057778 is 87775087.

It can be written as a sum of positive squares in 2 ways, for example, as 73908409 + 4149369 = 8597^2 + 2037^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-3 number, since 3×78057778³ (a number of 25 digits) contains 333 as substring.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1147875 + ... + 1147942.

Almost surely, 2^78057778 is an apocalyptic number.

78057778 is a deficient number, since it is larger than the sum of its proper divisors (45916394).

78057778 is a wasteful number, since it uses less digits than its factorization.

78057778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2295836.

The product of its (nonzero) digits is 768320, while the sum is 49.

The square root of 78057778 is about 8835.0312959265. The cubic root of 78057778 is about 427.3713402825.

The spelling of 78057778 in words is "seventy-eight million, fifty-seven thousand, seven hundred seventy-eight".