679440 has 80 divisors (see below), whose sum is σ = 2232000. Its totient is φ = 170496.

The previous prime is 679433. The next prime is 679451. The reversal of 679440 is 44976.

679440 = 33² + 34² + ... + 127².

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 679398 and 679407.

It is an unprimeable number.

679440 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 15 ways as a sum of consecutive naturals, for example, 4486 + ... + 4634.

It is an arithmetic number, because the mean of its divisors is an integer number (27900).

2⁶⁷⁹⁴⁴⁰ is an apocalyptic number.

679440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 679440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1116000).

679440 is an abundant number, since it is smaller than the sum of its proper divisors (1552560).

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

679440 is a wasteful number, since it uses less digits than its factorization.

679440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184 (or 178 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 679440 is about 824.2815053124. The cubic root of 679440 is about 87.9124473566.

The spelling of 679440 in words is "six hundred seventy-nine thousand, four hundred forty".