704640 has 64 divisors (see below), whose sum is σ = 2252160. Its totient is φ = 187392.

The previous prime is 704617. The next prime is 704647. The reversal of 704640 is 46407.

It is a tau number, because it is divible by the number of its divisors (64).

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (704647) by changing a digit.

704640 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1737 + ... + 2103.

It is an arithmetic number, because the mean of its divisors is an integer number (35190).

2⁷⁰⁴⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 704640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1126080).

704640 is an abundant number, since it is smaller than the sum of its proper divisors (1547520).

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

704640 is a wasteful number, since it uses less digits than its factorization.

704640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 389 (or 377 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 704640 is about 839.4283769328. The cubic root of 704640 is about 88.9861527924.

The spelling of 704640 in words is "seven hundred four thousand, six hundred forty".