123187913321 has 4 divisors (see below), whose sum is σ = 134386814544. Its totient is φ = 111989012100.

The previous prime is 123187913309. The next prime is 123187913347. The reversal of 123187913321 is 123319781321.

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, and also an emirpimes, since its reverse is a distinct semiprime: 123319781321 = 11 ⋅11210889211.

It is a cyclic number.

It is not a de Polignac number, because 123187913321 - 2³⁰ = 122114171497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123187913371) 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, 5599450595 + ... + 5599450616.

It is an arithmetic number, because the mean of its divisors is an integer number (33596703636).

Almost surely, 2^123187913321 is an apocalyptic number.

123187913321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

123187913321 is a deficient number, since it is larger than the sum of its proper divisors (11198901223).

123187913321 is a wasteful number, since it uses less digits than its factorization.

123187913321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11198901222.

The product of its digits is 54432, while the sum is 41.

The spelling of 123187913321 in words is "one hundred twenty-three billion, one hundred eighty-seven million, nine hundred thirteen thousand, three hundred twenty-one".