71373931281 has 81 divisors (see below), whose sum is σ = 112427963739. Its totient is φ = 43625996064.

The previous prime is 71373931201. The next prime is 71373931303. The reversal of 71373931281 is 18213937317.

The square root of 71373931281 is 267159.

It is a perfect power (a square), and thus also a powerful number.

71373931281 is a `hidden beast` number, since 7 + 137 + 393 + 128 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 49747287681 + 21626643600 = 223041^2 + 147060^2 .

It is not a de Polignac number, because 71373931281 - 2²³ = 71365542673 is a prime.

It is a super-2 number, since 2×71373931281² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (71373931201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 654806655 + ... + 654806763.

Almost surely, 2^71373931281 is an apocalyptic number.

71373931281 is the 267159-th square number.

71373931281 is the 133580-th centered octagonal number.

It is an amenable number.

71373931281 is a deficient number, since it is larger than the sum of its proper divisors (41054032458).

71373931281 is a wasteful number, since it uses less digits than its factorization.

71373931281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 348 (or 174 counting only the distinct ones).

The product of its digits is 190512, while the sum is 45.

The spelling of 71373931281 in words is "seventy-one billion, three hundred seventy-three million, nine hundred thirty-one thousand, two hundred eighty-one".