20545123 has 4 divisors (see below), whose sum is σ = 20702088. Its totient is φ = 20388160.

The previous prime is 20545097. The next prime is 20545127. The reversal of 20545123 is 32154502.

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 20545123 - 2⁹ = 20544611 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20545094 and 20545103.

It is not an unprimeable number, because it can be changed into a prime (20545127) 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, 78286 + ... + 78547.

It is an arithmetic number, because the mean of its divisors is an integer number (5175522).

Almost surely, 2^20545123 is an apocalyptic number.

20545123 is a deficient number, since it is larger than the sum of its proper divisors (156965).

20545123 is a wasteful number, since it uses less digits than its factorization.

20545123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156964.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 20545123 is about 4532.6728317848. The cubic root of 20545123 is about 273.8858414097.

Adding to 20545123 its reverse (32154502), we get a palindrome (52699625).

The spelling of 20545123 in words is "twenty million, five hundred forty-five thousand, one hundred twenty-three".