708721 has 4 divisors (see below), whose sum is σ = 763252. Its totient is φ = 654192.

The previous prime is 708703. The next prime is 708733. The reversal of 708721 is 127807.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 390625 + 318096 = 625^2 + 564^2 .

It is a cyclic number.

It is not a de Polignac number, because 708721 - 2⁵ = 708689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (708751) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27246 + ... + 27271.

It is an arithmetic number, because the mean of its divisors is an integer number (190813).

2⁷⁰⁸⁷²¹ is an apocalyptic number.

It is an amenable number.

708721 is a deficient number, since it is larger than the sum of its proper divisors (54531).

708721 is a wasteful number, since it uses less digits than its factorization.

708721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54530.

The product of its (nonzero) digits is 784, while the sum is 25.

The square root of 708721 is about 841.8556883457. The cubic root of 708721 is about 89.1576132344.

The spelling of 708721 in words is "seven hundred eight thousand, seven hundred twenty-one".