634878 has 20 divisors (see below), whose sum is σ = 1422960. Its totient is φ = 211572.

The previous prime is 634871. The next prime is 634891. The reversal of 634878 is 878436.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (634871) by changing a digit.

634878 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 1798 + ... + 2121.

It is an arithmetic number, because the mean of its divisors is an integer number (71148).

2⁶³⁴⁸⁷⁸ is an apocalyptic number.

634878 is an abundant number, since it is smaller than the sum of its proper divisors (788082).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

634878 is a wasteful number, since it uses less digits than its factorization.

634878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3933 (or 3924 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 634878 is about 796.7923192401. The cubic root of 634878 is about 85.9468754289.

The spelling of 634878 in words is "six hundred thirty-four thousand, eight hundred seventy-eight".