660256321 has 8 divisors (see below), whose sum is σ = 681861888. Its totient is φ = 638670000.

The previous prime is 660256309. The next prime is 660256339. The reversal of 660256321 is 123652066.

660256321 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 660256321 - 2²¹ = 658159169 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (660256301) 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, 105171 + ... + 111271.

It is an arithmetic number, because the mean of its divisors is an integer number (85232736).

Almost surely, 2^660256321 is an apocalyptic number.

It is an amenable number.

660256321 is a deficient number, since it is larger than the sum of its proper divisors (21605567).

660256321 is a wasteful number, since it uses less digits than its factorization.

660256321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9623.

The product of its (nonzero) digits is 12960, while the sum is 31.

The square root of 660256321 is about 25695.4533137674. The cubic root of 660256321 is about 870.7714657044.

The spelling of 660256321 in words is "six hundred sixty million, two hundred fifty-six thousand, three hundred twenty-one".