81036029065 has 4 divisors (see below), whose sum is σ = 97243234884. Its totient is φ = 64828823248.

The previous prime is 81036029051. The next prime is 81036029089. The reversal of 81036029065 is 56092063018.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9344895561 + 71691133504 = 96669^2 + 267752^2 .

It is a cyclic number.

It is not a de Polignac number, because 81036029065 - 2³⁵ = 46676290697 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8103602902 + ... + 8103602911.

It is an arithmetic number, because the mean of its divisors is an integer number (24310808721).

Almost surely, 2^81036029065 is an apocalyptic number.

It is an amenable number.

81036029065 is a deficient number, since it is larger than the sum of its proper divisors (16207205819).

81036029065 is a wasteful number, since it uses less digits than its factorization.

81036029065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16207205818.

The product of its (nonzero) digits is 77760, while the sum is 40.

The spelling of 81036029065 in words is "eighty-one billion, thirty-six million, twenty-nine thousand, sixty-five".