71293806081 has 9 divisors (see below), whose sum is σ = 102981099169. Its totient is φ = 47528670036.

The previous prime is 71293806053. The next prime is 71293806119. The reversal of 71293806081 is 18060839217.

The square root of 71293806081 is 267009.

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

71293806081 is a `hidden beast` number, since 7 + 1 + 2 + 9 + 38 + 0 + 608 + 1 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 71293806081 - 2¹⁷ = 71293675009 is a prime.

It is a super-2 number, since 2×71293806081² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71293806041) 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 8 ways as a sum of consecutive naturals, for example, 756526 + ... + 845528.

Almost surely, 2^71293806081 is an apocalyptic number.

71293806081 is the 267009-th square number.

71293806081 is the 133505-th centered octagonal number.

It is an amenable number.

71293806081 is a deficient number, since it is larger than the sum of its proper divisors (31687293088).

71293806081 is an frugal number, since it uses more digits than its factorization.

71293806081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178012 (or 89006 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The spelling of 71293806081 in words is "seventy-one billion, two hundred ninety-three million, eight hundred six thousand, eighty-one".