708021 has 10 divisors (see below), whose sum is σ = 1057782. Its totient is φ = 471960.

The previous prime is 708017. The next prime is 708023. The reversal of 708021 is 120807.

Added to its reverse (120807) it gives a triangular number (828828 = T₁₂₈₇).

It can be written as a sum of positive squares in only one way, i.e., 505521 + 202500 = 711^2 + 450^2 .

It is not a de Polignac number, because 708021 - 2² = 708017 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 707985 and 708003.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 708021.

It is not an unprimeable number, because it can be changed into a prime (708023) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 4290 + ... + 4451.

2⁷⁰⁸⁰²¹ is an apocalyptic number.

It is an amenable number.

708021 is a deficient number, since it is larger than the sum of its proper divisors (349761).

708021 is an equidigital number, since it uses as much as digits as its factorization.

708021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8753 (or 8744 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 708021 is about 841.4398374215. The cubic root of 708021 is about 89.1282500633.

Adding to 708021 its reverse (120807), we get a palindrome (828828).

The spelling of 708021 in words is "seven hundred eight thousand, twenty-one".