51686845 has 16 divisors (see below), whose sum is σ = 73330560. Its totient is φ = 34219584.

The previous prime is 51686779. The next prime is 51686849. The reversal of 51686845 is 54868615.

It is not a de Polignac number, because 51686845 - 2¹⁷ = 51555773 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51686849) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24447 + ... + 26476.

It is an arithmetic number, because the mean of its divisors is an integer number (4583160).

Almost surely, 2^51686845 is an apocalyptic number.

It is an amenable number.

51686845 is a deficient number, since it is larger than the sum of its proper divisors (21643715).

51686845 is a wasteful number, since it uses less digits than its factorization.

51686845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50964.

The product of its digits is 230400, while the sum is 43.

The square root of 51686845 is about 7189.3563689666. The cubic root of 51686845 is about 372.5003408252.

The spelling of 51686845 in words is "fifty-one million, six hundred eighty-six thousand, eight hundred forty-five".