51717839 has 4 divisors (see below), whose sum is σ = 51904824. Its totient is φ = 51530856.

The previous prime is 51717833. The next prime is 51717871. The reversal of 51717839 is 93871715.

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 51717839 - 2²⁴ = 34940623 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 51717796 and 51717805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51717833) 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, 93077 + ... + 93630.

It is an arithmetic number, because the mean of its divisors is an integer number (12976206).

Almost surely, 2^51717839 is an apocalyptic number.

51717839 is a deficient number, since it is larger than the sum of its proper divisors (186985).

51717839 is a wasteful number, since it uses less digits than its factorization.

51717839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186984.

The product of its digits is 52920, while the sum is 41.

The square root of 51717839 is about 7191.5115935386. The cubic root of 51717839 is about 372.5747825174.

The spelling of 51717839 in words is "fifty-one million, seven hundred seventeen thousand, eight hundred thirty-nine".