71421281 has 2 divisors, whose sum is σ = 71421282. Its totient is φ = 71421280.

The previous prime is 71421277. The next prime is 71421283. The reversal of 71421281 is 18212417.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68890000 + 2531281 = 8300^2 + 1591^2 .

It is an emirp because it is prime and its reverse (18212417) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71421281 - 2² = 71421277 is a prime.

It is a super-2 number, since 2×71421281² = 10201998759361922, which contains 22 as substring.

Together with 71421283, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 71421281.

It is not a weakly prime, because it can be changed into another prime (71421283) 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 as a sum of consecutive naturals, namely, 35710640 + 35710641.

It is an arithmetic number, because the mean of its divisors is an integer number (35710641).

Almost surely, 2^71421281 is an apocalyptic number.

It is an amenable number.

71421281 is a deficient number, since it is larger than the sum of its proper divisors (1).

71421281 is an equidigital number, since it uses as much as digits as its factorization.

71421281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 896, while the sum is 26.

The square root of 71421281 is about 8451.1112287083. Note that the first 3 decimals coincide. The cubic root of 71421281 is about 414.8991500237.

Adding to 71421281 its reverse (18212417), we get a palindrome (89633698).

The spelling of 71421281 in words is "seventy-one million, four hundred twenty-one thousand, two hundred eighty-one".