660640968 has 128 divisors (see below), whose sum is σ = 1990800000. Its totient is φ = 201782016.

The previous prime is 660640943. The next prime is 660640973. The reversal of 660640968 is 869046066.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 417603 + ... + 419181.

It is an arithmetic number, because the mean of its divisors is an integer number (15553125).

Almost surely, 2^660640968 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 660640968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (995400000).

660640968 is an abundant number, since it is smaller than the sum of its proper divisors (1330159032).

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

660640968 is a wasteful number, since it uses less digits than its factorization.

660640968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1756 (or 1746 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 45.

The square root of 660640968 is about 25702.9369528076. The cubic root of 660640968 is about 870.9405286376.

It can be divided in two parts, 6606 and 40968, that added together give a palindrome (47574).

The spelling of 660640968 in words is "six hundred sixty million, six hundred forty thousand, nine hundred sixty-eight".