720889840 has 80 divisors (see below), whose sum is σ = 1871058816. Its totient is φ = 256032000.

The previous prime is 720889781. The next prime is 720889847. The reversal of 720889840 is 48988027.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×720889840² = 1039364322830451200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720889847) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28315 + ... + 47365.

Almost surely, 2^720889840 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 720889840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (935529408).

720889840 is an abundant number, since it is smaller than the sum of its proper divisors (1150168976).

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

720889840 is a wasteful number, since it uses less digits than its factorization.

720889840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19118 (or 19112 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 46.

The square root of 720889840 is about 26849.3917994431. The cubic root of 720889840 is about 896.6500318604.

The spelling of 720889840 in words is "seven hundred twenty million, eight hundred eighty-nine thousand, eight hundred forty".