20503723 has 4 divisors (see below), whose sum is σ = 20532960. Its totient is φ = 20474488.

The previous prime is 20503709. The next prime is 20503753. The reversal of 20503723 is 32730502.

It is a happy number.

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 20503723 - 2²¹ = 18406571 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20503694 and 20503703.

It is not an unprimeable number, because it can be changed into a prime (20503753) 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, 13540 + ... + 14977.

It is an arithmetic number, because the mean of its divisors is an integer number (5133240).

Almost surely, 2^20503723 is an apocalyptic number.

20503723 is a deficient number, since it is larger than the sum of its proper divisors (29237).

20503723 is an equidigital number, since it uses as much as digits as its factorization.

20503723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29236.

The product of its (nonzero) digits is 1260, while the sum is 22.

The square root of 20503723 is about 4528.1036869754. The cubic root of 20503723 is about 273.7017507035.

The spelling of 20503723 in words is "twenty million, five hundred three thousand, seven hundred twenty-three".