51081 has 4 divisors (see below), whose sum is σ = 68112. Its totient is φ = 34052.

The previous prime is 51071. The next prime is 51109. The reversal of 51081 is 18015.

It is a happy number.

51081 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51081 - 2¹¹ = 49033 is a prime.

It is a super-2 number, since 2×51081² = 5218537122, which contains 22 as substring.

It is a D-number.

51081 is a modest number, since divided by 81 gives 51 as remainder.

It is a plaindrome in base 12 and base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 51081.

It is not an unprimeable number, because it can be changed into a prime (51001) 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, 8511 + ... + 8516.

It is an arithmetic number, because the mean of its divisors is an integer number (17028).

2⁵¹⁰⁸¹ is an apocalyptic number.

It is an amenable number.

51081 is a deficient number, since it is larger than the sum of its proper divisors (17031).

51081 is a wasteful number, since it uses less digits than its factorization.

51081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17030.

The product of its (nonzero) digits is 40, while the sum is 15.

The square root of 51081 is about 226.0110616762. The cubic root of 51081 is about 37.1039201714.

Adding to 51081 its reverse (18015), we get a palindrome (69096).

The spelling of 51081 in words is "fifty-one thousand, eighty-one".