51242 has 4 divisors (see below), whose sum is σ = 76866. Its totient is φ = 25620.

The previous prime is 51241. The next prime is 51257. The reversal of 51242 is 24215.

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

It can be written as a sum of positive squares in only one way, i.e., 48841 + 2401 = 221^2 + 49^2 .

It is not an unprimeable number, because it can be changed into a prime (51241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12809 + ... + 12812.

2⁵¹²⁴² is an apocalyptic number.

51242 is a deficient number, since it is larger than the sum of its proper divisors (25624).

51242 is a wasteful number, since it uses less digits than its factorization.

51242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25623.

The product of its digits is 80, while the sum is 14.

The square root of 51242 is about 226.3669587197. The cubic root of 51242 is about 37.1428613694.

Adding to 51242 its reverse (24215), we get a palindrome (75457).

The spelling of 51242 in words is "fifty-one thousand, two hundred forty-two".