20010131123 has 4 divisors (see below), whose sum is σ = 20880136848. Its totient is φ = 19140125400.

The previous prime is 20010131117. The next prime is 20010131171. The reversal of 20010131123 is 32113101002.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20010131123 - 2⁴ = 20010131107 is a prime.

It is a super-2 number, since 2×20010131123² (a number of 21 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 = 20010131098 and 20010131107.

It is not an unprimeable number, because it can be changed into a prime (20010131023) 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, 435002828 + ... + 435002873.

It is an arithmetic number, because the mean of its divisors is an integer number (5220034212).

Almost surely, 2^20010131123 is an apocalyptic number.

20010131123 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

20010131123 is a deficient number, since it is larger than the sum of its proper divisors (870005725).

20010131123 is an equidigital number, since it uses as much as digits as its factorization.

20010131123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 870005724.

The product of its (nonzero) digits is 36, while the sum is 14.

Adding to 20010131123 its reverse (32113101002), we get a palindrome (52123232125).

The spelling of 20010131123 in words is "twenty billion, ten million, one hundred thirty-one thousand, one hundred twenty-three".