720045 has 12 divisors (see below), whose sum is σ = 1248156. Its totient is φ = 384000.

The previous prime is 720023. The next prime is 720053. The reversal of 720045 is 540027.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 447561 + 272484 = 669^2 + 522^2 .

It is not a de Polignac number, because 720045 - 2⁶ = 719981 is a prime.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7956 + ... + 8045.

It is an arithmetic number, because the mean of its divisors is an integer number (104013).

2⁷²⁰⁰⁴⁵ is an apocalyptic number.

It is an amenable number.

720045 is a deficient number, since it is larger than the sum of its proper divisors (528111).

720045 is a wasteful number, since it uses less digits than its factorization.

720045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16012 (or 16009 counting only the distinct ones).

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

The square root of 720045 is about 848.5546535138. The cubic root of 720045 is about 89.6299621442.

Subtracting from 720045 its sum of digits (18), we obtain a palindrome (720027).

The spelling of 720045 in words is "seven hundred twenty thousand, forty-five".