20936939 has 4 divisors (see below), whose sum is σ = 20997624. Its totient is φ = 20876256.

The previous prime is 20936933. The next prime is 20936947. The reversal of 20936939 is 93963902.

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 20936939 - 2⁸ = 20936683 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20936896 and 20936905.

It is not an unprimeable number, because it can be changed into a prime (20936933) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29822 + ... + 30515.

It is an arithmetic number, because the mean of its divisors is an integer number (5249406).

Almost surely, 2^20936939 is an apocalyptic number.

20936939 is a deficient number, since it is larger than the sum of its proper divisors (60685).

20936939 is an equidigital number, since it uses as much as digits as its factorization.

20936939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60684.

The product of its (nonzero) digits is 78732, while the sum is 41.

The square root of 20936939 is about 4575.6900026116. The cubic root of 20936939 is about 275.6159811975.

The spelling of 20936939 in words is "twenty million, nine hundred thirty-six thousand, nine hundred thirty-nine".