720445440 has 448 divisors, whose sum is σ = 2774362752. Its totient is φ = 157286400.

The previous prime is 720445433. The next prime is 720445447. The reversal of 720445440 is 44544027.

It is an interprime number because it is at equal distance from previous prime (720445433) and next prime (720445447).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 720445398 and 720445407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720445447) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17571820 + ... + 17571860.

It is an arithmetic number, because the mean of its divisors is an integer number (6192774).

Almost surely, 2^720445440 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 720445440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1387181376).

720445440 is an abundant number, since it is smaller than the sum of its proper divisors (2053917312).

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

720445440 is a wasteful number, since it uses less digits than its factorization.

720445440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99 (or 75 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 30.

The square root of 720445440 is about 26841.1147309496. The cubic root of 720445440 is about 896.4657442569.

Adding to 720445440 its reverse (44544027), we get a palindrome (764989467).

The spelling of 720445440 in words is "seven hundred twenty million, four hundred forty-five thousand, four hundred forty".