51687767 has 4 divisors (see below), whose sum is σ = 51729096. Its totient is φ = 51646440.

The previous prime is 51687761. The next prime is 51687791. The reversal of 51687767 is 76778615.

51687767 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 76778615 = 5 ⋅15355723.

It is a cyclic number.

It is not a de Polignac number, because 51687767 - 2²² = 47493463 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 (51687761) 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 3 ways as a sum of consecutive naturals, for example, 18728 + ... + 21309.

It is an arithmetic number, because the mean of its divisors is an integer number (12932274).

Almost surely, 2^51687767 is an apocalyptic number.

51687767 is a deficient number, since it is larger than the sum of its proper divisors (41329).

51687767 is a wasteful number, since it uses less digits than its factorization.

51687767 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41328.

The product of its digits is 493920, while the sum is 47.

The square root of 51687767 is about 7189.4204912496. The cubic root of 51687767 is about 372.5025557232.

The spelling of 51687767 in words is "fifty-one million, six hundred eighty-seven thousand, seven hundred sixty-seven".