720663840 has 288 divisors, whose sum is σ = 2677265136. Its totient is φ = 175472640.

The previous prime is 720663829. The next prime is 720663857. The reversal of 720663840 is 48366027.

It can be written as a sum of positive squares in 8 ways, for example, as 265950864 + 454712976 = 16308^2 + 21324^2 .

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-3 number, since 3×720663840³ (a number of 28 digits) contains 333 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 720663795 and 720663804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2564500 + ... + 2564780.

Almost surely, 2^720663840 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 720663840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1338632568).

720663840 is an abundant number, since it is smaller than the sum of its proper divisors (1956601296).

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

720663840 is a wasteful number, since it uses less digits than its factorization.

720663840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 452 (or 441 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 720663840 is about 26845.1828080943. The cubic root of 720663840 is about 896.5563217094.

The spelling of 720663840 in words is "seven hundred twenty million, six hundred sixty-three thousand, eight hundred forty".