20431002121 has 8 divisors (see below), whose sum is σ = 20772059144. Its totient is φ = 20090142720.

The previous prime is 20431002013. The next prime is 20431002127. The reversal of 20431002121 is 12120013402.

It can be written as a sum of positive squares in 4 ways, for example, as 1309643721 + 19121358400 = 36189^2 + 138280^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20431002121 - 2⁷ = 20431001993 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20431002095 and 20431002104.

It is not an unprimeable number, because it can be changed into a prime (20431002127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 166921 + ... + 262153.

It is an arithmetic number, because the mean of its divisors is an integer number (2596507393).

Almost surely, 2^20431002121 is an apocalyptic number.

It is an amenable number.

20431002121 is a deficient number, since it is larger than the sum of its proper divisors (341057023).

20431002121 is an equidigital number, since it uses as much as digits as its factorization.

20431002121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98811.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 20431002121 its reverse (12120013402), we get a palindrome (32551015523).

The spelling of 20431002121 in words is "twenty billion, four hundred thirty-one million, two thousand, one hundred twenty-one".