720138240 has 156 divisors (see below), whose sum is σ = 2496813384. Its totient is φ = 191987712.

The previous prime is 720138217. The next prime is 720138253. The reversal of 720138240 is 42831027.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 182367 + ... + 186273.

It is an arithmetic number, because the mean of its divisors is an integer number (16005214).

Almost surely, 2^720138240 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 720138240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1248406692).

720138240 is an abundant number, since it is smaller than the sum of its proper divisors (1776675144).

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

720138240 is a wasteful number, since it uses less digits than its factorization.

720138240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3942 (or 3917 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 720138240 is about 26835.3915566738. The cubic root of 720138240 is about 896.3383076214.

Adding to 720138240 its reverse (42831027), we get a palindrome (762969267).

The spelling of 720138240 in words is "seven hundred twenty million, one hundred thirty-eight thousand, two hundred forty".