666256500 has 288 divisors, whose sum is σ = 2588441856. Its totient is φ = 140486400.

The previous prime is 666256483. The next prime is 666256511. The reversal of 666256500 is 5652666.

666256500 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 408687 + ... + 410313.

Almost surely, 2^666256500 is an apocalyptic number.

666256500 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 666256500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1294220928).

666256500 is an abundant number, since it is smaller than the sum of its proper divisors (1922185356).

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

666256500 is a wasteful number, since it uses less digits than its factorization.

666256500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1672 (or 1657 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The square root of 666256500 is about 25811.9449092857. The cubic root of 666256500 is about 873.4012711880.

The spelling of 666256500 in words is "six hundred sixty-six million, two hundred fifty-six thousand, five hundred".