20209873 has 4 divisors (see below), whose sum is σ = 20238400. Its totient is φ = 20181348.

The previous prime is 20209841. The next prime is 20209883. The reversal of 20209873 is 37890202.

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 20209873 - 2⁵ = 20209841 is a prime.

It is a super-2 number, since 2×20209873² = 816877933352258, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20209883) 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, 13173 + ... + 14626.

It is an arithmetic number, because the mean of its divisors is an integer number (5059600).

Almost surely, 2^20209873 is an apocalyptic number.

It is an amenable number.

20209873 is a deficient number, since it is larger than the sum of its proper divisors (28527).

20209873 is an equidigital number, since it uses as much as digits as its factorization.

20209873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28526.

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 20209873 is about 4495.5392335069. The cubic root of 20209873 is about 272.3879313598.

The spelling of 20209873 in words is "twenty million, two hundred nine thousand, eight hundred seventy-three".