51338681 has 2 divisors, whose sum is σ = 51338682. Its totient is φ = 51338680.

The previous prime is 51338669. The next prime is 51338687. The reversal of 51338681 is 18683315.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50183056 + 1155625 = 7084^2 + 1075^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51338681 is a prime.

It is a super-2 number, since 2×51338681² = 5271320333639522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51338687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25669340 + 25669341.

It is an arithmetic number, because the mean of its divisors is an integer number (25669341).

Almost surely, 2^51338681 is an apocalyptic number.

It is an amenable number.

51338681 is a deficient number, since it is larger than the sum of its proper divisors (1).

51338681 is an equidigital number, since it uses as much as digits as its factorization.

51338681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17280, while the sum is 35.

The square root of 51338681 is about 7165.1016043040. The cubic root of 51338681 is about 371.6620649576.

The spelling of 51338681 in words is "fifty-one million, three hundred thirty-eight thousand, six hundred eighty-one".