720918 has 36 divisors (see below), whose sum is σ = 1722084. Its totient is φ = 217800.

The previous prime is 720913. The next prime is 720931. The reversal of 720918 is 819027.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 720891 and 720900.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720913) by changing a digit.

720918 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 17 ways as a sum of consecutive naturals, for example, 2013 + ... + 2343.

2⁷²⁰⁹¹⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 720918, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (861042).

720918 is an abundant number, since it is smaller than the sum of its proper divisors (1001166).

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

720918 is a wasteful number, since it uses less digits than its factorization.

720918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361 (or 347 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 720918 is about 849.0689017977. The cubic root of 720918 is about 89.6661706939. Note that the first 3 decimals are identical.

It can be divided in two parts, 7209 and 18, that added together give a palindrome (7227).

The spelling of 720918 in words is "seven hundred twenty thousand, nine hundred eighteen".