77778734923 has 4 divisors (see below), whose sum is σ = 77811736320. Its totient is φ = 77745733528.

The previous prime is 77778734903. The next prime is 77778734933. The reversal of 77778734923 is 32943787777.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77778734923 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77778734903) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16497163 + ... + 16501876.

It is an arithmetic number, because the mean of its divisors is an integer number (19452934080).

Almost surely, 2^77778734923 is an apocalyptic number.

77778734923 is a deficient number, since it is larger than the sum of its proper divisors (33001397).

77778734923 is a wasteful number, since it uses less digits than its factorization.

77778734923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33001396.

The product of its digits is 87127488, while the sum is 64.

The spelling of 77778734923 in words is "seventy-seven billion, seven hundred seventy-eight million, seven hundred thirty-four thousand, nine hundred twenty-three".