721602 has 64 divisors (see below), whose sum is σ = 1935360. Its totient is φ = 194832.

The previous prime is 721597. The next prime is 721613. The reversal of 721602 is 206127.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

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 721602.

It is an unprimeable 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 31 ways as a sum of consecutive naturals, for example, 8653 + ... + 8735.

It is an arithmetic number, because the mean of its divisors is an integer number (30240).

2⁷²¹⁶⁰² is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 721602, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (967680).

721602 is an abundant number, since it is smaller than the sum of its proper divisors (1213758).

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

721602 is a wasteful number, since it uses less digits than its factorization.

721602 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124 (or 118 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 721602 is about 849.4716004670. The cubic root of 721602 is about 89.6945198607.

Adding to 721602 its reverse (206127), we get a palindrome (927729).

It can be divided in two parts, 7 and 21602, that added together give a square (21609 = 147²).

The spelling of 721602 in words is "seven hundred twenty-one thousand, six hundred two".