123544544643881 has 2 divisors, whose sum is σ = 123544544643882. Its totient is φ = 123544544643880.

The previous prime is 123544544643859. The next prime is 123544544643931. The reversal of 123544544643881 is 188346445445321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 105817842768400 + 17726701875481 = 10286780^2 + 4210309^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123544544643881 is a prime.

It is a super-2 number, since 2×123544544643881² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (123544544643811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61772272321940 + 61772272321941.

It is an arithmetic number, because the mean of its divisors is an integer number (61772272321941).

Almost surely, 2^{123544544643881} is an apocalyptic number.

It is an amenable number.

123544544643881 is a deficient number, since it is larger than the sum of its proper divisors (1).

123544544643881 is an equidigital number, since it uses as much as digits as its factorization.

123544544643881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 176947200, while the sum is 62.

The spelling of 123544544643881 in words is "one hundred twenty-three trillion, five hundred forty-four billion, five hundred forty-four million, six hundred forty-three thousand, eight hundred eighty-one".