51811489 has 2 divisors, whose sum is σ = 51811490. Its totient is φ = 51811488.

The previous prime is 51811453. The next prime is 51811519. The reversal of 51811489 is 98411815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29343889 + 22467600 = 5417^2 + 4740^2 .

It is a cyclic number.

It is not a de Polignac number, because 51811489 - 2¹¹ = 51809441 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (51814489) 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, 25905744 + 25905745.

It is an arithmetic number, because the mean of its divisors is an integer number (25905745).

Almost surely, 2^51811489 is an apocalyptic number.

It is an amenable number.

51811489 is a deficient number, since it is larger than the sum of its proper divisors (1).

51811489 is an equidigital number, since it uses as much as digits as its factorization.

51811489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11520, while the sum is 37.

The square root of 51811489 is about 7198.0197971387. The cubic root of 51811489 is about 372.7995314614.

It can be divided in two parts, 5181 and 1489, that added together give a triangular number (6670 = T₁₁₅).

The spelling of 51811489 in words is "fifty-one million, eight hundred eleven thousand, four hundred eighty-nine".