660772640 has 192 divisors, whose sum is σ = 1785732480. Its totient is φ = 228925440.

The previous prime is 660772639. The next prime is 660772649. The reversal of 660772640 is 46277066.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 660772594 and 660772603.

It is not an unprimeable number, because it can be changed into a prime (660772649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4753691 + ... + 4753829.

It is an arithmetic number, because the mean of its divisors is an integer number (9300690).

Almost surely, 2^660772640 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 660772640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (892866240).

660772640 is an abundant number, since it is smaller than the sum of its proper divisors (1124959840).

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

660772640 is a wasteful number, since it uses less digits than its factorization.

660772640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275 (or 267 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 38.

The square root of 660772640 is about 25705.4982445390. The cubic root of 660772640 is about 870.9983870250.

The spelling of 660772640 in words is "six hundred sixty million, seven hundred seventy-two thousand, six hundred forty".