21220131123 has 24 divisors (see below), whose sum is σ = 30943270800. Its totient is φ = 14012167680.

The previous prime is 21220131091. The next prime is 21220131143. The reversal of 21220131123 is 32113102212.

It is not a de Polignac number, because 21220131123 - 2⁵ = 21220131091 is a prime.

It is a super-2 number, since 2×21220131123² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21220131096 and 21220131105.

It is not an unprimeable number, because it can be changed into a prime (21220131143) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1721743 + ... + 1734023.

It is an arithmetic number, because the mean of its divisors is an integer number (1289302950).

Almost surely, 2^21220131123 is an apocalyptic number.

21220131123 is a deficient number, since it is larger than the sum of its proper divisors (9723139677).

21220131123 is a wasteful number, since it uses less digits than its factorization.

21220131123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14099 (or 14096 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21220131123 its reverse (32113102212), we get a palindrome (53333233335).

The spelling of 21220131123 in words is "twenty-one billion, two hundred twenty million, one hundred thirty-one thousand, one hundred twenty-three".