721560660 has 48 divisors (see below), whose sum is σ = 2036299776. Its totient is φ = 190899072.

The previous prime is 721560649. The next prime is 721560673. The reversal of 721560660 is 66065127.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39727 + ... + 54966.

It is an arithmetic number, because the mean of its divisors is an integer number (42422912).

Almost surely, 2^721560660 is an apocalyptic number.

It is an amenable number.

721560660 is an abundant number, since it is smaller than the sum of its proper divisors (1314739116).

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

721560660 is a wasteful number, since it uses less digits than its factorization.

721560660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94832 (or 94830 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 33.

The square root of 721560660 is about 26861.8811701638. The cubic root of 721560660 is about 896.9280698564.

The spelling of 721560660 in words is "seven hundred twenty-one million, five hundred sixty thousand, six hundred sixty".