123131121221 has 8 divisors (see below), whose sum is σ = 126009020544. Its totient is φ = 120253875840.

The previous prime is 123131121133. The next prime is 123131121229. The reversal of 123131121221 is 122121131321.

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

It is a cyclic number.

It is not a de Polignac number, because 123131121221 - 2¹⁸ = 123130859077 is a prime.

It is a super-2 number, since 2×123131121221² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 123131121193 and 123131121202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123131121229) 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, 228341 + ... + 546261.

It is an arithmetic number, because the mean of its divisors is an integer number (15751127568).

Almost surely, 2^123131121221 is an apocalyptic number.

It is an amenable number.

123131121221 is a deficient number, since it is larger than the sum of its proper divisors (2877899323).

123131121221 is an equidigital number, since it uses as much as digits as its factorization.

123131121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 326971.

The product of its digits is 144, while the sum is 20.

Adding to 123131121221 its reverse (122121131321), we get a palindrome (245252252542).

The spelling of 123131121221 in words is "one hundred twenty-three billion, one hundred thirty-one million, one hundred twenty-one thousand, two hundred twenty-one".