20783923 has 4 divisors (see below), whose sum is σ = 21500640. Its totient is φ = 20067208.

The previous prime is 20783887. The next prime is 20783941. The reversal of 20783923 is 32938702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32938702 = 2 ⋅16469351.

It is a cyclic number.

It is not a de Polignac number, because 20783923 - 2¹³ = 20775731 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20783953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 358315 + ... + 358372.

It is an arithmetic number, because the mean of its divisors is an integer number (5375160).

Almost surely, 2^20783923 is an apocalyptic number.

20783923 is a deficient number, since it is larger than the sum of its proper divisors (716717).

20783923 is an equidigital number, since it uses as much as digits as its factorization.

20783923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 716716.

The product of its (nonzero) digits is 18144, while the sum is 34.

The square root of 20783923 is about 4558.9388019582. The cubic root of 20783923 is about 274.9428994393.

The spelling of 20783923 in words is "twenty million, seven hundred eighty-three thousand, nine hundred twenty-three".