720810 has 24 divisors (see below), whose sum is σ = 1874340. Its totient is φ = 192192.

The previous prime is 720793. The next prime is 720829. The reversal of 720810 is 18027.

It can be written as a sum of positive squares in 2 ways, for example, as 720801 + 9 = 849^2 + 3^2 .

It is a super-2 number, since 2×720810² = 1039134112200, which contains 22 as substring.

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

720810 is a modest number, since divided by 810 gives 720 as remainder.

It is a zygodrome in base 4.

It is an unprimeable number.

720810 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 11 ways as a sum of consecutive naturals, for example, 3915 + ... + 4094.

2⁷²⁰⁸¹⁰ is an apocalyptic number.

720810 is an abundant number, since it is smaller than the sum of its proper divisors (1153530).

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

720810 is a wasteful number, since it uses less digits than its factorization.

720810 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8022 (or 8019 counting only the distinct ones).

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

The square root of 720810 is about 849.0053003368. The cubic root of 720810 is about 89.6616928707.

Adding to 720810 its reverse (18027), we get a palindrome (738837).

The spelling of 720810 in words is "seven hundred twenty thousand, eight hundred ten".