678787393 has 4 divisors (see below), whose sum is σ = 679234608. Its totient is φ = 678340180.

The previous prime is 678787391. The next prime is 678787411. The reversal of 678787393 is 393787876.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 678787393 - 2¹ = 678787391 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (678787391) 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, 221323 + ... + 224368.

It is an arithmetic number, because the mean of its divisors is an integer number (169808652).

Almost surely, 2^678787393 is an apocalyptic number.

It is an amenable number.

678787393 is a deficient number, since it is larger than the sum of its proper divisors (447215).

678787393 is a wasteful number, since it uses less digits than its factorization.

678787393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 447214.

The product of its digits is 10668672, while the sum is 58.

The square root of 678787393 is about 26053.5485682853. The cubic root of 678787393 is about 878.8429149433.

The spelling of 678787393 in words is "six hundred seventy-eight million, seven hundred eighty-seven thousand, three hundred ninety-three".