66418131 has 24 divisors (see below), whose sum is σ = 96895344. Its totient is φ = 40227840.

The previous prime is 66418127. The next prime is 66418139. The reversal of 66418131 is 13181466.

It is not a de Polignac number, because 66418131 - 2² = 66418127 is a prime.

It is a super-2 number, since 2×66418131² = 8822736251066322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66418139) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 366861 + ... + 367041.

It is an arithmetic number, because the mean of its divisors is an integer number (4037306).

Almost surely, 2^66418131 is an apocalyptic number.

66418131 is a deficient number, since it is larger than the sum of its proper divisors (30477213).

66418131 is a wasteful number, since it uses less digits than its factorization.

66418131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391 (or 294 counting only the distinct ones).

The product of its digits is 3456, while the sum is 30.

The square root of 66418131 is about 8149.7319587824. The cubic root of 66418131 is about 404.9756241997.

Adding to 66418131 its reverse (13181466), we get a palindrome (79599597).

The spelling of 66418131 in words is "sixty-six million, four hundred eighteen thousand, one hundred thirty-one".