123111661321 has 8 divisors (see below), whose sum is σ = 140142919104. Its totient is φ = 107053618320.

The previous prime is 123111661307. The next prime is 123111661333. The reversal of 123111661321 is 123166111321.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 123111661321 - 2⁹ = 123111660809 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 123111661321.

It is not an unprimeable number, because it can be changed into a prime (123111661381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 243303426 + ... + 243303931.

It is an arithmetic number, because the mean of its divisors is an integer number (17517864888).

Almost surely, 2^123111661321 is an apocalyptic number.

123111661321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

123111661321 is a deficient number, since it is larger than the sum of its proper divisors (17031257783).

123111661321 is a wasteful number, since it uses less digits than its factorization.

123111661321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 486607391.

The product of its digits is 1296, while the sum is 28.

Adding to 123111661321 its reverse (123166111321), we get a palindrome (246277772642).

The spelling of 123111661321 in words is "one hundred twenty-three billion, one hundred eleven million, six hundred sixty-one thousand, three hundred twenty-one".