77856705 has 12 divisors (see below), whose sum is σ = 134951700. Its totient is φ = 41523552.

The previous prime is 77856697. The next prime is 77856733. The reversal of 77856705 is 50765877.

It can be written as a sum of positive squares in 2 ways, for example, as 48566961 + 29289744 = 6969^2 + 5412^2 .

It is not a de Polignac number, because 77856705 - 2³ = 77856697 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 1730149 = 77856705 / (7 + 7 + 8 + 5 + 6 + 7 + 0 + 5).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 865030 + ... + 865119.

It is an arithmetic number, because the mean of its divisors is an integer number (11245975).

Almost surely, 2^77856705 is an apocalyptic number.

It is an amenable number.

77856705 is a deficient number, since it is larger than the sum of its proper divisors (57094995).

77856705 is a wasteful number, since it uses less digits than its factorization.

77856705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1730160 (or 1730157 counting only the distinct ones).

The product of its (nonzero) digits is 411600, while the sum is 45.

The square root of 77856705 is about 8823.6446551298. The cubic root of 77856705 is about 427.0040622151.

The spelling of 77856705 in words is "seventy-seven million, eight hundred fifty-six thousand, seven hundred five".