660778830840 has 256 divisors, whose sum is σ = 2055931084800. Its totient is φ = 169765134336.

The previous prime is 660778830823. The next prime is 660778830863. The reversal of 660778830840 is 48038877066.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 443772816 + ... + 443774304.

It is an arithmetic number, because the mean of its divisors is an integer number (8030980800).

Almost surely, 2^660778830840 is an apocalyptic number.

660778830840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 660778830840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1027965542400).

660778830840 is an abundant number, since it is smaller than the sum of its proper divisors (1395152253960).

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

660778830840 is a wasteful number, since it uses less digits than its factorization.

660778830840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2454 (or 2450 counting only the distinct ones).

The product of its (nonzero) digits is 10838016, while the sum is 57.

The spelling of 660778830840 in words is "six hundred sixty billion, seven hundred seventy-eight million, eight hundred thirty thousand, eight hundred forty".