51561233 has 2 divisors, whose sum is σ = 51561234. Its totient is φ = 51561232.

The previous prime is 51561203. The next prime is 51561241. The reversal of 51561233 is 33216515.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29724304 + 21836929 = 5452^2 + 4673^2 .

It is a cyclic number.

It is not a de Polignac number, because 51561233 - 2¹⁴ = 51544849 is a prime.

It is not a weakly prime, because it can be changed into another prime (51561203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25780616 + 25780617.

It is an arithmetic number, because the mean of its divisors is an integer number (25780617).

Almost surely, 2^51561233 is an apocalyptic number.

It is an amenable number.

51561233 is a deficient number, since it is larger than the sum of its proper divisors (1).

51561233 is an equidigital number, since it uses as much as digits as its factorization.

51561233 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2700, while the sum is 26.

The square root of 51561233 is about 7180.6150850745. The cubic root of 51561233 is about 372.1983396209.

Adding to 51561233 its reverse (33216515), we get a palindrome (84777748).

The spelling of 51561233 in words is "fifty-one million, five hundred sixty-one thousand, two hundred thirty-three".