656675389440 has 1440 divisors, whose sum is σ = 2786337912960. Its totient is φ = 146257477632.

The previous prime is 656675389417. The next prime is 656675389451. The reversal of 656675389440 is 44983576656.

656675389440 is a `hidden beast` number, since 6 + 5 + 6 + 6 + 7 + 538 + 94 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1440).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 7911751639 + ... + 7911751721.

It is an arithmetic number, because the mean of its divisors is an integer number (1934956884).

Almost surely, 2^656675389440 is an apocalyptic number.

656675389440 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 656675389440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1393168956480).

656675389440 is an abundant number, since it is smaller than the sum of its proper divisors (2129662523520).

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

656675389440 is an equidigital number, since it uses as much as digits as its factorization.

656675389440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212 (or 173 counting only the distinct ones).

The product of its (nonzero) digits is 130636800, while the sum is 63.

The spelling of 656675389440 in words is "six hundred fifty-six billion, six hundred seventy-five million, three hundred eighty-nine thousand, four hundred forty".