51191 has 8 divisors (see below), whose sum is σ = 59904. Its totient is φ = 42840.

The previous prime is 51169. The next prime is 51193. The reversal of 51191 is 19115.

51191 = 39² + 40² + ... + 59².

It is a happy number.

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

It is not a de Polignac number, because 51191 - 2¹⁴ = 34807 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 (51193) 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, 446 + ... + 548.

It is an arithmetic number, because the mean of its divisors is an integer number (7488).

2⁵¹¹⁹¹ is an apocalyptic number.

51191 is a deficient number, since it is larger than the sum of its proper divisors (8713).

51191 is a wasteful number, since it uses less digits than its factorization.

51191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181.

The product of its digits is 45, while the sum is 17.

The square root of 51191 is about 226.2542817274. The cubic root of 51191 is about 37.1305347966.

It can be divided in two parts, 51 and 191, that added together give a palindrome (242).

The spelling of 51191 in words is "fifty-one thousand, one hundred ninety-one".