51081871 has 4 divisors (see below), whose sum is σ = 51096312. Its totient is φ = 51067432.

The previous prime is 51081851. The next prime is 51081911. The reversal of 51081871 is 17818015.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 51081871 - 2⁷ = 51081743 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 (51081851) 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, 2076 + ... + 10318.

It is an arithmetic number, because the mean of its divisors is an integer number (12774078).

Almost surely, 2^51081871 is an apocalyptic number.

51081871 is a deficient number, since it is larger than the sum of its proper divisors (14441).

51081871 is an equidigital number, since it uses as much as digits as its factorization.

51081871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14440.

The product of its (nonzero) digits is 2240, while the sum is 31.

The square root of 51081871 is about 7147.1582464641. The cubic root of 51081871 is about 371.0413106088.

Adding to 51081871 its reverse (17818015), we get a palindrome (68899886).

The spelling of 51081871 in words is "fifty-one million, eighty-one thousand, eight hundred seventy-one".