123513104021221 has 4 divisors (see below), whose sum is σ = 123513353496000. Its totient is φ = 123512854546444.

The previous prime is 123513104021171. The next prime is 123513104021239. The reversal of 123513104021221 is 122120401315321.

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 123513104021221 - 2⁷ = 123513104021093 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 123513104021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123513104021521) 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 in 3 ways as a sum of consecutive naturals, for example, 123993271 + ... + 124985428.

It is an arithmetic number, because the mean of its divisors is an integer number (30878338374000).

Almost surely, 2^{123513104021221} is an apocalyptic number.

It is an amenable number.

123513104021221 is a deficient number, since it is larger than the sum of its proper divisors (249474779).

123513104021221 is an equidigital number, since it uses as much as digits as its factorization.

123513104021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249474778.

The product of its (nonzero) digits is 2880, while the sum is 28.

Adding to 123513104021221 its reverse (122120401315321), we get a palindrome (245633505336542).

The spelling of 123513104021221 in words is "one hundred twenty-three trillion, five hundred thirteen billion, one hundred four million, twenty-one thousand, two hundred twenty-one".