51129687 has 12 divisors (see below), whose sum is σ = 79303416. Its totient is φ = 29216880.

The previous prime is 51129679. The next prime is 51129733. The reversal of 51129687 is 78692115.

51129687 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 51129687 - 2³ = 51129679 is a prime.

It is a super-2 number, since 2×51129687² = 5228489785435938, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51129647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 173764 + ... + 174057.

It is an arithmetic number, because the mean of its divisors is an integer number (6608618).

Almost surely, 2^51129687 is an apocalyptic number.

51129687 is a deficient number, since it is larger than the sum of its proper divisors (28173729).

51129687 is a wasteful number, since it uses less digits than its factorization.

51129687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347838 (or 347831 counting only the distinct ones).

The product of its digits is 30240, while the sum is 39.

The square root of 51129687 is about 7150.5025697499. The cubic root of 51129687 is about 371.1570475492.

The spelling of 51129687 in words is "fifty-one million, one hundred twenty-nine thousand, six hundred eighty-seven".