123640124085281 has 4 divisors (see below), whose sum is σ = 125205188947200. Its totient is φ = 122075059223364.

The previous prime is 123640124085211. The next prime is 123640124085301. The reversal of 123640124085281 is 182580421046321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 123640124085281 - 2¹⁸ = 123640123823137 is a prime.

It is a super-2 number, since 2×123640124085281² (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 (123640124085211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 782532430841 + ... + 782532430998.

It is an arithmetic number, because the mean of its divisors is an integer number (31301297236800).

Almost surely, 2^{123640124085281} is an apocalyptic number.

It is an amenable number.

123640124085281 is a deficient number, since it is larger than the sum of its proper divisors (1565064861919).

123640124085281 is an equidigital number, since it uses as much as digits as its factorization.

123640124085281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1565064861918.

The product of its (nonzero) digits is 737280, while the sum is 47.

The spelling of 123640124085281 in words is "one hundred twenty-three trillion, six hundred forty billion, one hundred twenty-four million, eighty-five thousand, two hundred eighty-one".