51271818 has 32 divisors (see below), whose sum is σ = 111249600. Its totient is φ = 15659136.

The previous prime is 51271789. The next prime is 51271819. The reversal of 51271818 is 81817215.

It is not an unprimeable number, because it can be changed into a prime (51271819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8478 + ... + 13206.

It is an arithmetic number, because the mean of its divisors is an integer number (3476550).

Almost surely, 2^51271818 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51271818, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55624800).

51271818 is an abundant number, since it is smaller than the sum of its proper divisors (59977782).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51271818 is a wasteful number, since it uses less digits than its factorization.

51271818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4886.

The product of its digits is 4480, while the sum is 33.

The square root of 51271818 is about 7160.4342047113. The cubic root of 51271818 is about 371.5006451711.

The spelling of 51271818 in words is "fifty-one million, two hundred seventy-one thousand, eight hundred eighteen".