20123512031 has 6 divisors (see below), whose sum is σ = 23408983440. Its totient is φ = 17248724556.

The previous prime is 20123511977. The next prime is 20123512033. The reversal of 20123512031 is 13021532102.

It is a de Polignac number, because none of the positive numbers 2^k-20123512031 is a prime.

It is a super-2 number, since 2×20123512031² (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 = 20123511994 and 20123512012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20123512033) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 205341911 + ... + 205342008.

It is an arithmetic number, because the mean of its divisors is an integer number (3901497240).

Almost surely, 2^20123512031 is an apocalyptic number.

20123512031 is a deficient number, since it is larger than the sum of its proper divisors (3285471409).

20123512031 is an equidigital number, since it uses as much as digits as its factorization.

20123512031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410683933 (or 410683926 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 20.

The spelling of 20123512031 in words is "twenty billion, one hundred twenty-three million, five hundred twelve thousand, thirty-one".