20091123 has 12 divisors (see below), whose sum is σ = 31253040. Its totient is φ = 12363696.

The previous prime is 20091119. The next prime is 20091163. The reversal of 20091123 is 32119002.

It is a happy number.

It is not a de Polignac number, because 20091123 - 2² = 20091119 is a prime.

It is a super-2 number, since 2×20091123² = 807306446802258, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20091096 and 20091105.

It is not an unprimeable number, because it can be changed into a prime (20091103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 85743 + ... + 85976.

It is an arithmetic number, because the mean of its divisors is an integer number (2604420).

Almost surely, 2^20091123 is an apocalyptic number.

20091123 is a deficient number, since it is larger than the sum of its proper divisors (11161917).

20091123 is a wasteful number, since it uses less digits than its factorization.

20091123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171738 (or 171735 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 20091123 is about 4482.3122381200. The cubic root of 20091123 is about 271.8533802864.

The spelling of 20091123 in words is "twenty million, ninety-one thousand, one hundred twenty-three".