66418491 has 8 divisors (see below), whose sum is σ = 88625680. Its totient is φ = 44245152.

The previous prime is 66418489. The next prime is 66418511. The reversal of 66418491 is 19481466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66418491 - 2¹ = 66418489 is a prime.

It is a super-2 number, since 2×66418491² = 8822831893434162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66418421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3460 + ... + 12033.

It is an arithmetic number, because the mean of its divisors is an integer number (11078210).

Almost surely, 2^66418491 is an apocalyptic number.

66418491 is a deficient number, since it is larger than the sum of its proper divisors (22207189).

66418491 is a wasteful number, since it uses less digits than its factorization.

66418491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16925.

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

The square root of 66418491 is about 8149.7540453685. The cubic root of 66418491 is about 404.9763558823.

The spelling of 66418491 in words is "sixty-six million, four hundred eighteen thousand, four hundred ninety-one".