51523865 has 12 divisors (see below), whose sum is σ = 64039404. Its totient is φ = 39794496.

The previous prime is 51523861. The next prime is 51523873. The reversal of 51523865 is 56832515.

It can be written as a sum of positive squares in 6 ways, for example, as 143641 + 51380224 = 379^2 + 7168^2 .

It is not a de Polignac number, because 51523865 - 2² = 51523861 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51523861) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1922 + ... + 10331.

It is an arithmetic number, because the mean of its divisors is an integer number (5336617).

Almost surely, 2^51523865 is an apocalyptic number.

It is an amenable number.

51523865 is a deficient number, since it is larger than the sum of its proper divisors (12515539).

51523865 is a wasteful number, since it uses less digits than its factorization.

51523865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12316 (or 12287 counting only the distinct ones).

The product of its digits is 36000, while the sum is 35.

The square root of 51523865 is about 7178.0126079577. The cubic root of 51523865 is about 372.1084033903.

The spelling of 51523865 in words is "fifty-one million, five hundred twenty-three thousand, eight hundred sixty-five".