655957680 has 240 divisors, whose sum is σ = 2385680640. Its totient is φ = 146045952.

The previous prime is 655957657. The next prime is 655957697. The reversal of 655957680 is 86759556.

It is a tau number, because it is divible by the number of its divisors (240).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4719051 + ... + 4719189.

It is an arithmetic number, because the mean of its divisors is an integer number (9940336).

Almost surely, 2^655957680 is an apocalyptic number.

655957680 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 655957680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1192840320).

655957680 is an abundant number, since it is smaller than the sum of its proper divisors (1729722960).

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

655957680 is a wasteful number, since it uses less digits than its factorization.

655957680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 268 (or 209 counting only the distinct ones).

The product of its (nonzero) digits is 2268000, while the sum is 51.

The square root of 655957680 is about 25611.6707772062. The cubic root of 655957680 is about 868.8776119494.

The spelling of 655957680 in words is "six hundred fifty-five million, nine hundred fifty-seven thousand, six hundred eighty".