51115839 has 4 divisors (see below), whose sum is σ = 68154456. Its totient is φ = 34077224.

The previous prime is 51115829. The next prime is 51115847. The reversal of 51115839 is 93851115.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51115839 - 2⁷ = 51115711 is a prime.

It is a super-2 number, since 2×51115839² = 5225657993347842, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51115829) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8519304 + ... + 8519309.

It is an arithmetic number, because the mean of its divisors is an integer number (17038614).

Almost surely, 2^51115839 is an apocalyptic number.

51115839 is a deficient number, since it is larger than the sum of its proper divisors (17038617).

51115839 is a wasteful number, since it uses less digits than its factorization.

51115839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17038616.

The product of its digits is 5400, while the sum is 33.

The square root of 51115839 is about 7149.5341806302. The cubic root of 51115839 is about 371.1235363793.

The spelling of 51115839 in words is "fifty-one million, one hundred fifteen thousand, eight hundred thirty-nine".