721867608 has 432 divisors, whose sum is σ = 2660931000. Its totient is φ = 175633920.

The previous prime is 721867591. The next prime is 721867609. The reversal of 721867608 is 806768127.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721867609) by changing a digit.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 8110828 + ... + 8110916.

Almost surely, 2^721867608 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 721867608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1330465500).

721867608 is an abundant number, since it is smaller than the sum of its proper divisors (1939063392).

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

721867608 is a wasteful number, since it uses less digits than its factorization.

721867608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156 (or 131 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 45.

The square root of 721867608 is about 26867.5940121180. The cubic root of 721867608 is about 897.0552346088.

The spelling of 721867608 in words is "seven hundred twenty-one million, eight hundred sixty-seven thousand, six hundred eight".