66555774 has 24 divisors (see below), whose sum is σ = 145694640. Its totient is φ = 21955968.

The previous prime is 66555773. The next prime is 66555781. The reversal of 66555774 is 47755566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66555773) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17314 + ... + 20805.

It is an arithmetic number, because the mean of its divisors is an integer number (6070610).

Almost surely, 2^66555774 is an apocalyptic number.

66555774 is an abundant number, since it is smaller than the sum of its proper divisors (79138866).

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

66555774 is a wasteful number, since it uses less digits than its factorization.

66555774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38224 (or 38221 counting only the distinct ones).

The product of its digits is 882000, while the sum is 45.

The square root of 66555774 is about 8158.1722217663. The cubic root of 66555774 is about 405.2551844001.

The spelling of 66555774 in words is "sixty-six million, five hundred fifty-five thousand, seven hundred seventy-four".