55666523640 has 256 divisors, whose sum is σ = 209913016320. Its totient is φ = 11495024640.

The previous prime is 55666523629. The next prime is 55666523669. The reversal of 55666523640 is 4632566655.

It is a self number, because there is not a number n which added to its sum of digits gives 55666523640.

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, 459010 + ... + 567470.

It is an arithmetic number, because the mean of its divisors is an integer number (819972720).

Almost surely, 2^55666523640 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 55666523640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104956508160).

55666523640 is an abundant number, since it is smaller than the sum of its proper divisors (154246492680).

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

55666523640 is a wasteful number, since it uses less digits than its factorization.

55666523640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108542 (or 108538 counting only the distinct ones).

The product of its (nonzero) digits is 3888000, while the sum is 48.

The spelling of 55666523640 in words is "fifty-five billion, six hundred sixty-six million, five hundred twenty-three thousand, six hundred forty".