20209001 has 4 divisors (see below), whose sum is σ = 20250000. Its totient is φ = 20168004.

The previous prime is 20208961. The next prime is 20209003. The reversal of 20209001 is 10090202.

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 20209001 - 2¹⁰ = 20207977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20209003) 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, 19751 + ... + 20748.

It is an arithmetic number, because the mean of its divisors is an integer number (5062500).

Almost surely, 2^20209001 is an apocalyptic number.

It is an amenable number.

20209001 is a deficient number, since it is larger than the sum of its proper divisors (40999).

20209001 is an equidigital number, since it uses as much as digits as its factorization.

20209001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40998.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 20209001 is about 4495.4422474324. The cubic root of 20209001 is about 272.3840137087.

Adding to 20209001 its reverse (10090202), we get a palindrome (30299203).

The spelling of 20209001 in words is "twenty million, two hundred nine thousand, one".