656066880 has 252 divisors, whose sum is σ = 2625585300. Its totient is φ = 149925888.

The previous prime is 656066863. The next prime is 656066893. The reversal of 656066880 is 88660656.

656066880 is a `hidden beast` number, since 6 + 560 + 6 + 6 + 8 + 80 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 484352064 + 171714816 = 22008^2 + 13104^2 .

It is a tau number, because it is divible by the number of its divisors (252).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 138796 + ... + 143444.

Almost surely, 2^656066880 is an apocalyptic number.

656066880 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 656066880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1312792650).

656066880 is an abundant number, since it is smaller than the sum of its proper divisors (1969518420).

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

656066880 is a wasteful number, since it uses less digits than its factorization.

656066880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4686 (or 4666 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The square root of 656066880 is about 25613.8025291053. The cubic root of 656066880 is about 868.9258244960.

The spelling of 656066880 in words is "six hundred fifty-six million, sixty-six thousand, eight hundred eighty".