81965893155 has 16 divisors (see below), whose sum is σ = 136847404800. Its totient is φ = 41814484448.

The previous prime is 81965893111. The next prime is 81965893199. The reversal of 81965893155 is 55139856918.

It is an interprime number because it is at equal distance from previous prime (81965893111) and next prime (81965893199).

It is a cyclic number.

It is not a de Polignac number, because 81965893155 - 2²⁵ = 81932338723 is a prime.

It is a Smith number, since the sum of its digits (60) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 118790805 + ... + 118791494.

It is an arithmetic number, because the mean of its divisors is an integer number (8552962800).

Almost surely, 2^81965893155 is an apocalyptic number.

81965893155 is a deficient number, since it is larger than the sum of its proper divisors (54881511645).

81965893155 is a wasteful number, since it uses less digits than its factorization.

81965893155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237582330.

The product of its digits is 11664000, while the sum is 60.

The spelling of 81965893155 in words is "eighty-one billion, nine hundred sixty-five million, eight hundred ninety-three thousand, one hundred fifty-five".