51818161 has 2 divisors, whose sum is σ = 51818162. Its totient is φ = 51818160.

The previous prime is 51818141. The next prime is 51818183. The reversal of 51818161 is 16181815.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44635761 + 7182400 = 6681^2 + 2680^2 .

It is a cyclic number.

It is not a de Polignac number, because 51818161 - 2⁷ = 51818033 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (51818141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25909080 + 25909081.

It is an arithmetic number, because the mean of its divisors is an integer number (25909081).

Almost surely, 2^51818161 is an apocalyptic number.

It is an amenable number.

51818161 is a deficient number, since it is larger than the sum of its proper divisors (1).

51818161 is an equidigital number, since it uses as much as digits as its factorization.

51818161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1920, while the sum is 31.

The square root of 51818161 is about 7198.4832430172. The cubic root of 51818161 is about 372.8155331357.

Adding to 51818161 its reverse (16181815), we get a palindrome (67999976).

The spelling of 51818161 in words is "fifty-one million, eight hundred eighteen thousand, one hundred sixty-one".