66394481 has 4 divisors (see below), whose sum is σ = 66430464. Its totient is φ = 66358500.

The previous prime is 66394429. The next prime is 66394483. The reversal of 66394481 is 18449366.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66394481 is a prime.

It is a super-2 number, since 2×66394481² = 8816454214518722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66394483) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15065 + ... + 18966.

It is an arithmetic number, because the mean of its divisors is an integer number (16607616).

Almost surely, 2^66394481 is an apocalyptic number.

It is an amenable number.

66394481 is a deficient number, since it is larger than the sum of its proper divisors (35983).

66394481 is a wasteful number, since it uses less digits than its factorization.

66394481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35982.

The product of its digits is 124416, while the sum is 41.

The square root of 66394481 is about 8148.2808616296. The cubic root of 66394481 is about 404.9275509282.

The spelling of 66394481 in words is "sixty-six million, three hundred ninety-four thousand, four hundred eighty-one".