51318591 has 8 divisors (see below), whose sum is σ = 69064704. Its totient is φ = 33892440.

The previous prime is 51318569. The next prime is 51318607. The reversal of 51318591 is 19581315.

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

It is a de Polignac number, because none of the positive numbers 2^k-51318591 is a prime.

It is a super-3 number, since 3×51318591³ (a number of 24 digits) contains 333 as substring.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51318551) 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, 79615 + ... + 80256.

It is an arithmetic number, because the mean of its divisors is an integer number (8633088).

Almost surely, 2^51318591 is an apocalyptic number.

51318591 is a deficient number, since it is larger than the sum of its proper divisors (17746113).

51318591 is a wasteful number, since it uses less digits than its factorization.

51318591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159981.

The product of its digits is 5400, while the sum is 33.

The square root of 51318591 is about 7163.6995330625. The cubic root of 51318591 is about 371.6135786771.

The spelling of 51318591 in words is "fifty-one million, three hundred eighteen thousand, five hundred ninety-one".