20432021 has 2 divisors, whose sum is σ = 20432022. Its totient is φ = 20432020.

The previous prime is 20432017. The next prime is 20432033. The reversal of 20432021 is 12023402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20151121 + 280900 = 4489^2 + 530^2 .

It is a cyclic number.

It is not a de Polignac number, because 20432021 - 2² = 20432017 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20431987 and 20432005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20432051) 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 as a sum of consecutive naturals, namely, 10216010 + 10216011.

It is an arithmetic number, because the mean of its divisors is an integer number (10216011).

Almost surely, 2^20432021 is an apocalyptic number.

It is an amenable number.

20432021 is a deficient number, since it is larger than the sum of its proper divisors (1).

20432021 is an equidigital number, since it uses as much as digits as its factorization.

20432021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 20432021 is about 4520.1793106026. The cubic root of 20432021 is about 273.3823309280.

Adding to 20432021 its reverse (12023402), we get a palindrome (32455423).

The spelling of 20432021 in words is "twenty million, four hundred thirty-two thousand, twenty-one".