720522 has 32 divisors (see below), whose sum is σ = 1748160. Its totient is φ = 218160.

The previous prime is 720497. The next prime is 720527. The reversal of 720522 is 225027.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 720495 and 720504.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 720522.

It is not an unprimeable number, because it can be changed into a prime (720527) by changing a digit.

720522 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13 + ... + 1200.

It is an arithmetic number, because the mean of its divisors is an integer number (54630).

2⁷²⁰⁵²² is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 720522, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (874080).

720522 is an abundant number, since it is smaller than the sum of its proper divisors (1027638).

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

720522 is a wasteful number, since it uses less digits than its factorization.

720522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1235 (or 1229 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 18.

The square root of 720522 is about 848.8356731429. The cubic root of 720522 is about 89.6497498217.

Adding to 720522 its reverse (225027), we get a palindrome (945549).

It can be divided in two parts, 7205 and 22, that added together give a palindrome (7227).

The spelling of 720522 in words is "seven hundred twenty thousand, five hundred twenty-two".