51251 has 4 divisors (see below), whose sum is σ = 52272. Its totient is φ = 50232.

The previous prime is 51241. The next prime is 51257. The reversal of 51251 is 15215.

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 51251 - 2¹⁰ = 50227 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a nialpdrome in base 16.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 51251.

It is not an unprimeable number, because it can be changed into a prime (51257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 431 + ... + 536.

It is an arithmetic number, because the mean of its divisors is an integer number (13068).

2⁵¹²⁵¹ is an apocalyptic number.

51251 is a deficient number, since it is larger than the sum of its proper divisors (1021).

51251 is an equidigital number, since it uses as much as digits as its factorization.

51251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1020.

The product of its digits is 50, while the sum is 14.

The square root of 51251 is about 226.3868370732. The cubic root of 51251 is about 37.1450357978.

Adding to 51251 its reverse (15215), we get a palindrome (66466).

The spelling of 51251 in words is "fifty-one thousand, two hundred fifty-one".