51591 has 8 divisors (see below), whose sum is σ = 71280. Its totient is φ = 33152.

The previous prime is 51581. The next prime is 51593. The reversal of 51591 is 19515.

It is a happy number.

51591 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 51591 - 2¹³ = 43399 is a prime.

It is a nialpdrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51593) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 210 + ... + 383.

It is an arithmetic number, because the mean of its divisors is an integer number (8910).

2⁵¹⁵⁹¹ is an apocalyptic number.

51591 is a deficient number, since it is larger than the sum of its proper divisors (19689).

51591 is a wasteful number, since it uses less digits than its factorization.

51591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 625.

The product of its digits is 225, while the sum is 21.

The square root of 51591 is about 227.1365228227. The cubic root of 51591 is about 37.2269950894.

It can be divided in two parts, 515 and 91, that added together give a palindrome (606).

The spelling of 51591 in words is "fifty-one thousand, five hundred ninety-one".