660496721 has 8 divisors (see below), whose sum is σ = 686712000. Its totient is φ = 634510800.

The previous prime is 660496717. The next prime is 660496729. The reversal of 660496721 is 127694066.

660496721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 660496721 - 2² = 660496717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (660496729) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51455 + ... + 62996.

It is an arithmetic number, because the mean of its divisors is an integer number (85839000).

Almost surely, 2^660496721 is an apocalyptic number.

It is an amenable number.

660496721 is a deficient number, since it is larger than the sum of its proper divisors (26215279).

660496721 is a wasteful number, since it uses less digits than its factorization.

660496721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114679.

The product of its (nonzero) digits is 108864, while the sum is 41.

The square root of 660496721 is about 25700.1307584222. The cubic root of 660496721 is about 870.8771358069.

The spelling of 660496721 in words is "six hundred sixty million, four hundred ninety-six thousand, seven hundred twenty-one".