66644292 has 96 divisors (see below), whose sum is σ = 185601024. Its totient is φ = 18345600.

The previous prime is 66644239. The next prime is 66644299. The reversal of 66644292 is 29244666.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 66644292.

It is not an unprimeable number, because it can be changed into a prime (66644299) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 121563 + ... + 122109.

It is an arithmetic number, because the mean of its divisors is an integer number (1933344).

Almost surely, 2^66644292 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 66644292, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92800512).

66644292 is an abundant number, since it is smaller than the sum of its proper divisors (118956732).

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

66644292 is a wasteful number, since it uses less digits than its factorization.

66644292 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 649 (or 647 counting only the distinct ones).

The product of its digits is 124416, while the sum is 39.

The square root of 66644292 is about 8163.5955313820. The cubic root of 66644292 is about 405.4347655484.

The spelling of 66644292 in words is "sixty-six million, six hundred forty-four thousand, two hundred ninety-two".