78728578 has 8 divisors (see below), whose sum is σ = 118158480. Its totient is φ = 39342420.

The previous prime is 78728549. The next prime is 78728593. The reversal of 78728578 is 87582787.

It is a happy number.

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

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, 5988 + ... + 13903.

It is an arithmetic number, because the mean of its divisors is an integer number (14769810).

Almost surely, 2^78728578 is an apocalyptic number.

78728578 is a deficient number, since it is larger than the sum of its proper divisors (39429902).

78728578 is a wasteful number, since it uses less digits than its factorization.

78728578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21872.

The product of its digits is 1756160, while the sum is 52.

The square root of 78728578 is about 8872.9125995921. The cubic root of 78728578 is about 428.5920744234.

The spelling of 78728578 in words is "seventy-eight million, seven hundred twenty-eight thousand, five hundred seventy-eight".