678990 has 32 divisors (see below), whose sum is σ = 1755936. Its totient is φ = 167040.

The previous prime is 678989. The next prime is 679033. The reversal of 678990 is 99876.

678990 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×678990² = 922054840200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 481 + ... + 1260.

It is an arithmetic number, because the mean of its divisors is an integer number (54873).

2⁶⁷⁸⁹⁹⁰ is an apocalyptic number.

678990 is an abundant number, since it is smaller than the sum of its proper divisors (1076946).

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

678990 is a wasteful number, since it uses less digits than its factorization.

678990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1764.

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 678990 is about 824.0084951018. The cubic root of 678990 is about 87.8930346352.

The spelling of 678990 in words is "six hundred seventy-eight thousand, nine hundred ninety".