77891755 has 4 divisors (see below), whose sum is σ = 93470112. Its totient is φ = 62313400.

The previous prime is 77891753. The next prime is 77891783. The reversal of 77891755 is 55719877.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 77891755 - 2¹ = 77891753 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77891699 and 77891708.

It is not an unprimeable number, because it can be changed into a prime (77891753) 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, 7789171 + ... + 7789180.

It is an arithmetic number, because the mean of its divisors is an integer number (23367528).

Almost surely, 2^77891755 is an apocalyptic number.

77891755 is a deficient number, since it is larger than the sum of its proper divisors (15578357).

77891755 is a wasteful number, since it uses less digits than its factorization.

77891755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15578356.

The product of its digits is 617400, while the sum is 49.

The square root of 77891755 is about 8825.6305723727. The cubic root of 77891755 is about 427.0681296881.

The spelling of 77891755 in words is "seventy-seven million, eight hundred ninety-one thousand, seven hundred fifty-five".