721208 has 16 divisors (see below), whose sum is σ = 1432080. Its totient is φ = 339328.

The previous prime is 721207. The next prime is 721213. The reversal of 721208 is 802127.

It is a self number, because there is not a number n which added to its sum of digits gives 721208.

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 721208.

It is not an unprimeable number, because it can be changed into a prime (721207) by changing a digit.

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, 2516 + ... + 2787.

It is an arithmetic number, because the mean of its divisors is an integer number (89505).

2⁷²¹²⁰⁸ is an apocalyptic number.

It is an amenable number.

721208 is a deficient number, since it is larger than the sum of its proper divisors (710872).

721208 is a wasteful number, since it uses less digits than its factorization.

721208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5326 (or 5322 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 20.

The square root of 721208 is about 849.2396599312. The cubic root of 721208 is about 89.6781922662.

It can be divided in two parts, 721 and 208, that added together give a palindrome (929).

The spelling of 721208 in words is "seven hundred twenty-one thousand, two hundred eight".