51508243 has 4 divisors (see below), whose sum is σ = 51652080. Its totient is φ = 51364408.

The previous prime is 51508241. The next prime is 51508253. The reversal of 51508243 is 34280515.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34280515 = 5 ⋅6856103.

It is a cyclic number.

It is not a de Polignac number, because 51508243 - 2¹ = 51508241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51508241) 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, 71380 + ... + 72097.

It is an arithmetic number, because the mean of its divisors is an integer number (12913020).

Almost surely, 2^51508243 is an apocalyptic number.

51508243 is a deficient number, since it is larger than the sum of its proper divisors (143837).

51508243 is a wasteful number, since it uses less digits than its factorization.

51508243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143836.

The product of its (nonzero) digits is 4800, while the sum is 28.

The square root of 51508243 is about 7176.9243412481. The cubic root of 51508243 is about 372.0707919191.

Adding to 51508243 its reverse (34280515), we get a palindrome (85788758).

The spelling of 51508243 in words is "fifty-one million, five hundred eight thousand, two hundred forty-three".