51319281 has 16 divisors (see below), whose sum is σ = 73817856. Its totient is φ = 31526016.

The previous prime is 51319231. The next prime is 51319283. The reversal of 51319281 is 18291315.

51319281 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 51319281 - 2⁷ = 51319153 is a prime.

It is a super-2 number, since 2×51319281² = 5267337204713922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51319283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42421 + ... + 43613.

It is an arithmetic number, because the mean of its divisors is an integer number (4613616).

Almost surely, 2^51319281 is an apocalyptic number.

It is an amenable number.

51319281 is a deficient number, since it is larger than the sum of its proper divisors (22498575).

51319281 is a wasteful number, since it uses less digits than its factorization.

51319281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2312.

The product of its digits is 2160, while the sum is 30.

The square root of 51319281 is about 7163.7476923744. The cubic root of 51319281 is about 371.6152441699.

The spelling of 51319281 in words is "fifty-one million, three hundred nineteen thousand, two hundred eighty-one".