51389517 has 4 divisors (see below), whose sum is σ = 68519360. Its totient is φ = 34259676.

The previous prime is 51389497. The next prime is 51389539. The reversal of 51389517 is 71598315.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2^k-51389517 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51389557) 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, 8564917 + ... + 8564922.

It is an arithmetic number, because the mean of its divisors is an integer number (17129840).

Almost surely, 2^51389517 is an apocalyptic number.

It is an amenable number.

51389517 is a deficient number, since it is larger than the sum of its proper divisors (17129843).

51389517 is a wasteful number, since it uses less digits than its factorization.

51389517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17129842.

The product of its digits is 37800, while the sum is 39.

The square root of 51389517 is about 7168.6481989284. The cubic root of 51389517 is about 371.7846988049.

The spelling of 51389517 in words is "fifty-one million, three hundred eighty-nine thousand, five hundred seventeen".