65731818 has 16 divisors (see below), whose sum is σ = 132302880. Its totient is φ = 21770736.

The previous prime is 65731817. The next prime is 65731829. The reversal of 65731818 is 81813756.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (65731817) 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, 33948 + ... + 35831.

It is an arithmetic number, because the mean of its divisors is an integer number (8268930).

Almost surely, 2^65731818 is an apocalyptic number.

65731818 is an abundant number, since it is smaller than the sum of its proper divisors (66571062).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65731818 is a wasteful number, since it uses less digits than its factorization.

65731818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69941.

The product of its digits is 40320, while the sum is 39.

The square root of 65731818 is about 8107.5161424446. The cubic root of 65731818 is about 403.5758914080.

The spelling of 65731818 in words is "sixty-five million, seven hundred thirty-one thousand, eight hundred eighteen".