66444700 has 72 divisors (see below), whose sum is σ = 171988992. Its totient is φ = 21785280.

The previous prime is 66444671. The next prime is 66444731. The reversal of 66444700 is 744466.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14037 + ... + 18163.

It is an arithmetic number, because the mean of its divisors is an integer number (2388736).

Almost surely, 2^66444700 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 66444700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85994496).

66444700 is an abundant number, since it is smaller than the sum of its proper divisors (105544292).

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

66444700 is a wasteful number, since it uses less digits than its factorization.

66444700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4171 (or 4164 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 31.

The square root of 66444700 is about 8151.3618494090. The cubic root of 66444700 is about 405.0296173026.

The spelling of 66444700 in words is "sixty-six million, four hundred forty-four thousand, seven hundred".