20421201 has 4 divisors (see below), whose sum is σ = 27228272. Its totient is φ = 13614132.

The previous prime is 20421187. The next prime is 20421209. The reversal of 20421201 is 10212402.

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 not a de Polignac number, because 20421201 - 2⁷ = 20421073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20421209) 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 3 ways as a sum of consecutive naturals, for example, 3403531 + ... + 3403536.

It is an arithmetic number, because the mean of its divisors is an integer number (6807068).

Almost surely, 2^20421201 is an apocalyptic number.

It is an amenable number.

20421201 is a deficient number, since it is larger than the sum of its proper divisors (6807071).

20421201 is an equidigital number, since it uses as much as digits as its factorization.

20421201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6807070.

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 20421201 is about 4518.9822969337. The cubic root of 20421201 is about 273.3340648734.

Adding to 20421201 its reverse (10212402), we get a palindrome (30633603).

The spelling of 20421201 in words is "twenty million, four hundred twenty-one thousand, two hundred one".