77930857 has 4 divisors (see below), whose sum is σ = 78053076. Its totient is φ = 77808640.

The previous prime is 77930851. The next prime is 77930861. The reversal of 77930857 is 75803977.

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: 75803977 = 19 ⋅3989683.

It can be written as a sum of positive squares in 2 ways, for example, as 46526041 + 31404816 = 6821^2 + 5604^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77930857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77930851) by changing a digit.

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, 60148 + ... + 61429.

It is an arithmetic number, because the mean of its divisors is an integer number (19513269).

Almost surely, 2^77930857 is an apocalyptic number.

It is an amenable number.

77930857 is a deficient number, since it is larger than the sum of its proper divisors (122219).

77930857 is a wasteful number, since it uses less digits than its factorization.

77930857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122218.

The product of its (nonzero) digits is 370440, while the sum is 46.

The square root of 77930857 is about 8827.8455469044. The cubic root of 77930857 is about 427.1395810864.

It can be divided in two parts, 77930 and 857, that added together give a palindrome (78787).

The spelling of 77930857 in words is "seventy-seven million, nine hundred thirty thousand, eight hundred fifty-seven".