51816239 has 2 divisors, whose sum is σ = 51816240. Its totient is φ = 51816238.

The previous prime is 51816229. The next prime is 51816241. The reversal of 51816239 is 93261815.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51816239 - 2¹² = 51812143 is a prime.

Together with 51816241, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 51816199 and 51816208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51816229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25908119 + 25908120.

It is an arithmetic number, because the mean of its divisors is an integer number (25908120).

Almost surely, 2^51816239 is an apocalyptic number.

51816239 is a deficient number, since it is larger than the sum of its proper divisors (1).

51816239 is an equidigital number, since it uses as much as digits as its factorization.

51816239 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12960, while the sum is 35.

The square root of 51816239 is about 7198.3497414338. The cubic root of 51816239 is about 372.8109236816.

The spelling of 51816239 in words is "fifty-one million, eight hundred sixteen thousand, two hundred thirty-nine".