78727885 has 4 divisors (see below), whose sum is σ = 94473468. Its totient is φ = 62982304.

The previous prime is 78727877. The next prime is 78727921. The reversal of 78727885 is 58872787.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58872787 = 1229 ⋅47903.

It can be written as a sum of positive squares in 2 ways, for example, as 40424164 + 38303721 = 6358^2 + 6189^2 .

It is a cyclic number.

It is not a de Polignac number, because 78727885 - 2³ = 78727877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 7872784 + ... + 7872793.

It is an arithmetic number, because the mean of its divisors is an integer number (23618367).

Almost surely, 2^78727885 is an apocalyptic number.

It is an amenable number.

78727885 is a deficient number, since it is larger than the sum of its proper divisors (15745583).

78727885 is a wasteful number, since it uses less digits than its factorization.

78727885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15745582.

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

The square root of 78727885 is about 8872.8735480677. The cubic root of 78727885 is about 428.5908168742.

The spelling of 78727885 in words is "seventy-eight million, seven hundred twenty-seven thousand, eight hundred eighty-five".