20090123 has 4 divisors (see below), whose sum is σ = 20580168. Its totient is φ = 19600080.

The previous prime is 20090099. The next prime is 20090129. The reversal of 20090123 is 32109002.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20090123 - 2²² = 15895819 is a prime.

It is a super-2 number, since 2×20090123² = 807226084310258, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20090129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 244961 + ... + 245042.

It is an arithmetic number, because the mean of its divisors is an integer number (5145042).

Almost surely, 2^20090123 is an apocalyptic number.

20090123 is a deficient number, since it is larger than the sum of its proper divisors (490045).

20090123 is an equidigital number, since it uses as much as digits as its factorization.

20090123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 490044.

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 20090123 is about 4482.2006871625. The cubic root of 20090123 is about 271.8488698717.

Adding to 20090123 its reverse (32109002), we get a palindrome (52199125).

The spelling of 20090123 in words is "twenty million, ninety thousand, one hundred twenty-three".