66417431 has 4 divisors (see below), whose sum is σ = 66693264. Its totient is φ = 66141600.

The previous prime is 66417391. The next prime is 66417443. The reversal of 66417431 is 13471466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13471466 = 2 ⋅6735733.

It is a cyclic number.

It is not a de Polignac number, because 66417431 - 2⁶ = 66417367 is a prime.

It is a super-2 number, since 2×66417431² = 8822550281279522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66417451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 137555 + ... + 138036.

It is an arithmetic number, because the mean of its divisors is an integer number (16673316).

Almost surely, 2^66417431 is an apocalyptic number.

66417431 is a deficient number, since it is larger than the sum of its proper divisors (275833).

66417431 is a wasteful number, since it uses less digits than its factorization.

66417431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275832.

The product of its digits is 12096, while the sum is 32.

The square root of 66417431 is about 8149.6890124716. The cubic root of 66417431 is about 404.9742014761.

Adding to 66417431 its reverse (13471466), we get a palindrome (79888897).

The spelling of 66417431 in words is "sixty-six million, four hundred seventeen thousand, four hundred thirty-one".