20123503 has 4 divisors (see below), whose sum is σ = 20132728. Its totient is φ = 20114280.

The previous prime is 20123483. The next prime is 20123507. The reversal of 20123503 is 30532102.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20123503 - 2¹⁷ = 19992431 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20123507) 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, 700 + ... + 6382.

It is an arithmetic number, because the mean of its divisors is an integer number (5033182).

Almost surely, 2^20123503 is an apocalyptic number.

20123503 is a deficient number, since it is larger than the sum of its proper divisors (9225).

20123503 is an equidigital number, since it uses as much as digits as its factorization.

20123503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9224.

The product of its (nonzero) digits is 180, while the sum is 16.

The square root of 20123503 is about 4485.9227590319. The cubic root of 20123503 is about 271.9993467040. Note that the first 3 decimals are identical.

Adding to 20123503 its reverse (30532102), we get a palindrome (50655605).

The spelling of 20123503 in words is "twenty million, one hundred twenty-three thousand, five hundred three".