51686347 has 4 divisors (see below), whose sum is σ = 51724440. Its totient is φ = 51648256.

The previous prime is 51686339. The next prime is 51686351. The reversal of 51686347 is 74368615.

It is a happy number.

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 51686347 - 2³ = 51686339 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51686317) 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, 16933 + ... + 19750.

It is an arithmetic number, because the mean of its divisors is an integer number (12931110).

Almost surely, 2^51686347 is an apocalyptic number.

51686347 is a deficient number, since it is larger than the sum of its proper divisors (38093).

51686347 is a wasteful number, since it uses less digits than its factorization.

51686347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38092.

The product of its digits is 120960, while the sum is 40.

The square root of 51686347 is about 7189.3217343502. The cubic root of 51686347 is about 372.4991444810.

The spelling of 51686347 in words is "fifty-one million, six hundred eighty-six thousand, three hundred forty-seven".