66194481 has 16 divisors (see below), whose sum is σ = 93744000. Its totient is φ = 41403648.

The previous prime is 66194477. The next prime is 66194489. The reversal of 66194481 is 18449166.

It is not a de Polignac number, because 66194481 - 2² = 66194477 is a prime.

It is a super-2 number, since 2×66194481² = 8763418629718722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66194489) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15940 + ... + 19658.

It is an arithmetic number, because the mean of its divisors is an integer number (5859000).

Almost surely, 2^66194481 is an apocalyptic number.

It is an amenable number.

66194481 is a deficient number, since it is larger than the sum of its proper divisors (27549519).

66194481 is a wasteful number, since it uses less digits than its factorization.

66194481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4088.

The product of its digits is 41472, while the sum is 39.

The square root of 66194481 is about 8135.9990781710. Note that the first 3 decimals coincide. The cubic root of 66194481 is about 404.5205544287.

The spelling of 66194481 in words is "sixty-six million, one hundred ninety-four thousand, four hundred eighty-one".