677778391 has 4 divisors (see below), whose sum is σ = 678477384. Its totient is φ = 677079400.

The previous prime is 677778373. The next prime is 677778397. The reversal of 677778391 is 193877776.

677778391 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 677778391 - 2²⁹ = 140907479 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (677778397) 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, 348040 + ... + 349981.

It is an arithmetic number, because the mean of its divisors is an integer number (169619346).

Almost surely, 2^677778391 is an apocalyptic number.

677778391 is a deficient number, since it is larger than the sum of its proper divisors (698993).

677778391 is an equidigital number, since it uses as much as digits as its factorization.

677778391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 698992.

The product of its digits is 3111696, while the sum is 55.

The square root of 677778391 is about 26034.1773636119. The cubic root of 677778391 is about 878.4072390054.

The spelling of 677778391 in words is "six hundred seventy-seven million, seven hundred seventy-eight thousand, three hundred ninety-one".