51421081 has 2 divisors, whose sum is σ = 51421082. Its totient is φ = 51421080.

The previous prime is 51421063. The next prime is 51421091. The reversal of 51421081 is 18012415.

51421081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42771600 + 8649481 = 6540^2 + 2941^2 .

It is a cyclic number.

It is not a de Polignac number, because 51421081 - 2²⁵ = 17866649 is a prime.

It is a super-2 number, since 2×51421081² = 5288255142417122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51421001) 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 as a sum of consecutive naturals, namely, 25710540 + 25710541.

It is an arithmetic number, because the mean of its divisors is an integer number (25710541).

Almost surely, 2^51421081 is an apocalyptic number.

It is an amenable number.

51421081 is a deficient number, since it is larger than the sum of its proper divisors (1).

51421081 is an equidigital number, since it uses as much as digits as its factorization.

51421081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 320, while the sum is 22.

The square root of 51421081 is about 7170.8493918085. The cubic root of 51421081 is about 371.8608012939.

Adding to 51421081 its reverse (18012415), we get a palindrome (69433496).

The spelling of 51421081 in words is "fifty-one million, four hundred twenty-one thousand, eighty-one".