678969877 has 4 divisors (see below), whose sum is σ = 679695436. Its totient is φ = 678244320.

The previous prime is 678969859. The next prime is 678969901. The reversal of 678969877 is 778969876.

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

It can be written as a sum of positive squares in 2 ways, for example, as 266636241 + 412333636 = 16329^2 + 20306^2 .

It is a cyclic number.

It is not a de Polignac number, because 678969877 - 2¹¹ = 678967829 is a prime.

It is a super-2 number, since 2×678969877² = 922000187746790258, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (678669877) 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, 361374 + ... + 363247.

It is an arithmetic number, because the mean of its divisors is an integer number (169923859).

Almost surely, 2^678969877 is an apocalyptic number.

It is an amenable number.

678969877 is a deficient number, since it is larger than the sum of its proper divisors (725559).

678969877 is an equidigital number, since it uses as much as digits as its factorization.

678969877 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 725558.

The product of its digits is 64012032, while the sum is 67.

The square root of 678969877 is about 26057.0504278593. The cubic root of 678969877 is about 878.9216634108.

Subtracting 678969877 from its reverse (778969876), we obtain a palindrome (99999999).

The spelling of 678969877 in words is "six hundred seventy-eight million, nine hundred sixty-nine thousand, eight hundred seventy-seven".