81862238225123 has 4 divisors (see below), whose sum is σ = 82706178825480. Its totient is φ = 81018297624768.

The previous prime is 81862238225059. The next prime is 81862238225171. The reversal of 81862238225123 is 32152283226818.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 81862238225123 - 2⁶ = 81862238225059 is a prime.

It is a super-2 number, since 2×81862238225123² (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 (81862238222123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 421970300033 + ... + 421970300226.

It is an arithmetic number, because the mean of its divisors is an integer number (20676544706370).

Almost surely, 2^{81862238225123} is an apocalyptic number.

81862238225123 is a deficient number, since it is larger than the sum of its proper divisors (843940600357).

81862238225123 is an equidigital number, since it uses as much as digits as its factorization.

81862238225123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 843940600356.

The product of its digits is 4423680, while the sum is 53.

The spelling of 81862238225123 in words is "eighty-one trillion, eight hundred sixty-two billion, two hundred thirty-eight million, two hundred twenty-five thousand, one hundred twenty-three".