20113431421 has 4 divisors (see below), whose sum is σ = 20120474332. Its totient is φ = 20106388512.

The previous prime is 20113431419. The next prime is 20113431431. The reversal of 20113431421 is 12413431102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12413431102 = 2 ⋅6206715551.

It can be written as a sum of positive squares in 2 ways, for example, as 11574747396 + 8538684025 = 107586^2 + 92405^2 .

It is a cyclic number.

It is not a de Polignac number, because 20113431421 - 2¹ = 20113431419 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20113431392 and 20113431401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20113431431) 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, 3517170 + ... + 3522883.

It is an arithmetic number, because the mean of its divisors is an integer number (5030118583).

Almost surely, 2^20113431421 is an apocalyptic number.

It is an amenable number.

20113431421 is a deficient number, since it is larger than the sum of its proper divisors (7042911).

20113431421 is an equidigital number, since it uses as much as digits as its factorization.

20113431421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7042910.

The product of its (nonzero) digits is 576, while the sum is 22.

Adding to 20113431421 its reverse (12413431102), we get a palindrome (32526862523).

The spelling of 20113431421 in words is "twenty billion, one hundred thirteen million, four hundred thirty-one thousand, four hundred twenty-one".