20123112421 has 4 divisors (see below), whose sum is σ = 20125242144. Its totient is φ = 20120982700.

The previous prime is 20123112409. The next prime is 20123112431. The reversal of 20123112421 is 12421132102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20123112421 - 2⁵ = 20123112389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20123112431) 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, 1050625 + ... + 1069606.

It is an arithmetic number, because the mean of its divisors is an integer number (5031310536).

Almost surely, 2^20123112421 is an apocalyptic number.

It is an amenable number.

20123112421 is a deficient number, since it is larger than the sum of its proper divisors (2129723).

20123112421 is an equidigital number, since it uses as much as digits as its factorization.

20123112421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2129722.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 20123112421 its reverse (12421132102), we get a palindrome (32544244523).

The spelling of 20123112421 in words is "twenty billion, one hundred twenty-three million, one hundred twelve thousand, four hundred twenty-one".