708821 has 4 divisors (see below), whose sum is σ = 710892. Its totient is φ = 706752.

The previous prime is 708803. The next prime is 708823. The reversal of 708821 is 128807.

708821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 128807 = 7 ⋅18401.

It can be written as a sum of positive squares in 2 ways, for example, as 46225 + 662596 = 215^2 + 814^2 .

It is a cyclic number.

It is not a de Polignac number, because 708821 - 2¹⁰ = 707797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (708823) 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, 386 + ... + 1251.

It is an arithmetic number, because the mean of its divisors is an integer number (177723).

2⁷⁰⁸⁸²¹ is an apocalyptic number.

It is an amenable number.

708821 is a deficient number, since it is larger than the sum of its proper divisors (2071).

708821 is a wasteful number, since it uses less digits than its factorization.

708821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2070.

The product of its (nonzero) digits is 896, while the sum is 26.

The square root of 708821 is about 841.9150788530. The cubic root of 708821 is about 89.1618063946.

The spelling of 708821 in words is "seven hundred eight thousand, eight hundred twenty-one".