720632640 has 448 divisors, whose sum is σ = 2879847936. Its totient is φ = 148635648.

The previous prime is 720632639. The next prime is 720632651. The reversal of 720632640 is 46236027.

It is a tau number, because it is divible by the number of its divisors (448).

It is a super-2 number, since 2×720632640² = 1038622803666739200, which contains 22 as substring.

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 = 720632598 and 720632607.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 6377224 + ... + 6377336.

It is an arithmetic number, because the mean of its divisors is an integer number (6428232).

Almost surely, 2^720632640 is an apocalyptic number.

720632640 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 720632640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1439923968).

720632640 is an abundant number, since it is smaller than the sum of its proper divisors (2159215296).

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

720632640 is a wasteful number, since it uses less digits than its factorization.

720632640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226 (or 216 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 30.

The square root of 720632640 is about 26844.6016919603. The cubic root of 720632640 is about 896.5433831938.

Adding to 720632640 its reverse (46236027), we get a palindrome (766868667).

The spelling of 720632640 in words is "seven hundred twenty million, six hundred thirty-two thousand, six hundred forty".