66656250 has 112 divisors (see below), whose sum is σ = 187497600. Its totient is φ = 17550000.

The previous prime is 66656243. The next prime is 66656257. The reversal of 66656250 is 5265666.

It is an interprime number because it is at equal distance from previous prime (66656243) and next prime (66656257).

It is not an unprimeable number, because it can be changed into a prime (66656257) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 843711 + ... + 843789.

Almost surely, 2^66656250 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66656250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93748800).

66656250 is an abundant number, since it is smaller than the sum of its proper divisors (120841350).

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

66656250 is an frugal number, since it uses more digits than its factorization.

66656250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120 (or 89 counting only the distinct ones).

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

The square root of 66656250 is about 8164.3278964040. The cubic root of 66656250 is about 405.4590131813.

The spelling of 66656250 in words is "sixty-six million, six hundred fifty-six thousand, two hundred fifty".