66244240 has 80 divisors (see below), whose sum is σ = 165739392. Its totient is φ = 24532992.

The previous prime is 66244229. The next prime is 66244253. The reversal of 66244240 is 4244266.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 66244199 and 66244208.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 90757 + ... + 91483.

Almost surely, 2^66244240 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 66244240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82869696).

66244240 is an abundant number, since it is smaller than the sum of its proper divisors (99495152).

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

66244240 is a wasteful number, since it uses less digits than its factorization.

66244240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 824 (or 818 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 28.

The square root of 66244240 is about 8139.0564563713. The cubic root of 66244240 is about 404.6218896482.

The spelling of 66244240 in words is "sixty-six million, two hundred forty-four thousand, two hundred forty".