705680 has 20 divisors (see below), whose sum is σ = 1640892. Its totient is φ = 282240.

The previous prime is 705643. The next prime is 705689. The reversal of 705680 is 86507.

It can be written as a sum of positive squares in 2 ways, for example, as 350464 + 355216 = 592^2 + 596^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (705689) by changing a digit.

705680 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 (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4331 + ... + 4490.

2⁷⁰⁵⁶⁸⁰ is an apocalyptic number.

It is an amenable number.

705680 is an abundant number, since it is smaller than the sum of its proper divisors (935212).

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

705680 is a wasteful number, since it uses less digits than its factorization.

705680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8834 (or 8828 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 705680 is about 840.0476176979. The cubic root of 705680 is about 89.0299104114.

The spelling of 705680 in words is "seven hundred five thousand, six hundred eighty".