81265812058081 has 64 divisors (see below), whose sum is σ = 97531108300800. Its totient is φ = 67650631319040.

The previous prime is 81265812058063. The next prime is 81265812058087. The reversal of 81265812058081 is 18085021856218.

It is not a de Polignac number, because 81265812058081 - 2²³ = 81265803669473 is a prime.

It is a super-2 number, since 2×81265812058081² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81265812058087) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7537867911 + ... + 7537878691.

It is an arithmetic number, because the mean of its divisors is an integer number (1523923567200).

Almost surely, 2^{81265812058081} is an apocalyptic number.

It is an amenable number.

81265812058081 is a deficient number, since it is larger than the sum of its proper divisors (16265296242719).

81265812058081 is a wasteful number, since it uses less digits than its factorization.

81265812058081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14399 (or 14385 counting only the distinct ones).

The product of its (nonzero) digits is 2457600, while the sum is 55.

The spelling of 81265812058081 in words is "eighty-one trillion, two hundred sixty-five billion, eight hundred twelve million, fifty-eight thousand, eighty-one".