51812881 has 2 divisors, whose sum is σ = 51812882. Its totient is φ = 51812880.

The previous prime is 51812843. The next prime is 51812903. The reversal of 51812881 is 18821815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51710481 + 102400 = 7191^2 + 320^2 .

It is a cyclic number.

It is not a de Polignac number, because 51812881 - 2¹¹ = 51810833 is a prime.

It is a super-2 number, since 2×51812881² = 5369149275040322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51812801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25906440 + 25906441.

It is an arithmetic number, because the mean of its divisors is an integer number (25906441).

Almost surely, 2^51812881 is an apocalyptic number.

It is an amenable number.

51812881 is a deficient number, since it is larger than the sum of its proper divisors (1).

51812881 is an equidigital number, since it uses as much as digits as its factorization.

51812881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5120, while the sum is 34.

The square root of 51812881 is about 7198.1164897492. The cubic root of 51812881 is about 372.8028700536.

The spelling of 51812881 in words is "fifty-one million, eight hundred twelve thousand, eight hundred eighty-one".