721617120 has 384 divisors, whose sum is σ = 2951424000. Its totient is φ = 164602368.

The previous prime is 721617119. The next prime is 721617151. The reversal of 721617120 is 21716127.

721617120 is a `hidden beast` number, since 7 + 21 + 617 + 1 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1481517 + ... + 1482003.

It is an arithmetic number, because the mean of its divisors is an integer number (7686000).

Almost surely, 2^721617120 is an apocalyptic number.

721617120 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 721617120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1475712000).

721617120 is an abundant number, since it is smaller than the sum of its proper divisors (2229806880).

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

721617120 is a wasteful number, since it uses less digits than its factorization.

721617120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 532 (or 504 counting only the distinct ones).

The product of its (nonzero) digits is 1176, while the sum is 27.

The square root of 721617120 is about 26862.9320812156. The cubic root of 721617120 is about 896.9514632410.

It can be divided in two parts, 7216 and 17120, that added together give a square (24336 = 156²).

The spelling of 721617120 in words is "seven hundred twenty-one million, six hundred seventeen thousand, one hundred twenty".