66784172 has 24 divisors (see below), whose sum is σ = 143843616. Its totient is φ = 26419968.

The previous prime is 66784153. The next prime is 66784219. The reversal of 66784172 is 27148766.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 91373 + ... + 92100.

It is an arithmetic number, because the mean of its divisors is an integer number (5993484).

Almost surely, 2^66784172 is an apocalyptic number.

It is an amenable number.

66784172 is an abundant number, since it is smaller than the sum of its proper divisors (77059444).

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

66784172 is a wasteful number, since it uses less digits than its factorization.

66784172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183497 (or 183495 counting only the distinct ones).

The product of its digits is 112896, while the sum is 41.

The square root of 66784172 is about 8172.1583440362. The cubic root of 66784172 is about 405.7182235994.

The spelling of 66784172 in words is "sixty-six million, seven hundred eighty-four thousand, one hundred seventy-two".