51138911 has 4 divisors (see below), whose sum is σ = 52328232. Its totient is φ = 49949592.

The previous prime is 51138887. The next prime is 51138917. The reversal of 51138911 is 11983115.

51138911 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51138911 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51138917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 594596 + ... + 594681.

It is an arithmetic number, because the mean of its divisors is an integer number (13082058).

Almost surely, 2^51138911 is an apocalyptic number.

51138911 is a deficient number, since it is larger than the sum of its proper divisors (1189321).

51138911 is a wasteful number, since it uses less digits than its factorization.

51138911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1189320.

The product of its digits is 1080, while the sum is 29.

The square root of 51138911 is about 7151.1475302919. The cubic root of 51138911 is about 371.1793656124.

The spelling of 51138911 in words is "fifty-one million, one hundred thirty-eight thousand, nine hundred eleven".