51245 has 8 divisors (see below), whose sum is σ = 63384. Its totient is φ = 39744.

The previous prime is 51241. The next prime is 51257. The reversal of 51245 is 54215.

It can be written as a sum of positive squares in 4 ways, for example, as 6724 + 44521 = 82^2 + 211^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 51245 - 2² = 51241 is a prime.

It is a Duffinian number.

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51241) 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 7 ways as a sum of consecutive naturals, for example, 47 + ... + 323.

It is an arithmetic number, because the mean of its divisors is an integer number (7923).

2⁵¹²⁴⁵ is an apocalyptic number.

51245 is the 185-th pentagonal number.

It is an amenable number.

51245 is a deficient number, since it is larger than the sum of its proper divisors (12139).

51245 is a wasteful number, since it uses less digits than its factorization.

51245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 319.

The product of its digits is 200, while the sum is 17.

The square root of 51245 is about 226.3735850315. The cubic root of 51245 is about 37.1435862072.

The spelling of 51245 in words is "fifty-one thousand, two hundred forty-five".