51561473 has 2 divisors, whose sum is σ = 51561474. Its totient is φ = 51561472.

The previous prime is 51561451. The next prime is 51561479. The reversal of 51561473 is 37416515.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48205249 + 3356224 = 6943^2 + 1832^2 .

It is a cyclic number.

It is not a de Polignac number, because 51561473 - 2¹⁰ = 51560449 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (51561479) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25780736 + 25780737.

It is an arithmetic number, because the mean of its divisors is an integer number (25780737).

Almost surely, 2^51561473 is an apocalyptic number.

It is an amenable number.

51561473 is a deficient number, since it is larger than the sum of its proper divisors (1).

51561473 is an equidigital number, since it uses as much as digits as its factorization.

51561473 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12600, while the sum is 32.

The square root of 51561473 is about 7180.6317967154. The cubic root of 51561473 is about 372.1989171056.

Adding to 51561473 its reverse (37416515), we get a palindrome (88977988).

The spelling of 51561473 in words is "fifty-one million, five hundred sixty-one thousand, four hundred seventy-three".