66418431 has 8 divisors (see below), whose sum is σ = 89385984. Its totient is φ = 43864920.

The previous prime is 66418427. The next prime is 66418489. The reversal of 66418431 is 13481466.

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

It is not a de Polignac number, because 66418431 - 2² = 66418427 is a prime.

It is a super-2 number, since 2×66418431² = 8822815953003522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 66418392 and 66418401.

It is a congruent number.

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

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 103135 + ... + 103776.

It is an arithmetic number, because the mean of its divisors is an integer number (11173248).

Almost surely, 2^66418431 is an apocalyptic number.

66418431 is a deficient number, since it is larger than the sum of its proper divisors (22967553).

66418431 is a wasteful number, since it uses less digits than its factorization.

66418431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207021.

The product of its digits is 13824, while the sum is 33.

The square root of 66418431 is about 8149.7503642750. The cubic root of 66418431 is about 404.9762339354.

Adding to 66418431 its reverse (13481466), we get a palindrome (79899897).

The spelling of 66418431 in words is "sixty-six million, four hundred eighteen thousand, four hundred thirty-one".