51313687 has 4 divisors (see below), whose sum is σ = 51518376. Its totient is φ = 51109000.

The previous prime is 51313643. The next prime is 51313697. The reversal of 51313687 is 78631315.

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 51313687 - 2¹⁹ = 50789399 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 (51313637) 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, 101968 + ... + 102469.

It is an arithmetic number, because the mean of its divisors is an integer number (12879594).

Almost surely, 2^51313687 is an apocalyptic number.

51313687 is a deficient number, since it is larger than the sum of its proper divisors (204689).

51313687 is a wasteful number, since it uses less digits than its factorization.

51313687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204688.

The product of its digits is 15120, while the sum is 34.

The square root of 51313687 is about 7163.3572436393. The cubic root of 51313687 is about 371.6017411799.

The spelling of 51313687 in words is "fifty-one million, three hundred thirteen thousand, six hundred eighty-seven".