20873539 has 2 divisors, whose sum is σ = 20873540. Its totient is φ = 20873538.

The previous prime is 20873537. The next prime is 20873563. The reversal of 20873539 is 93537802.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20873539 - 2¹ = 20873537 is a prime.

Together with 20873537, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 20873498 and 20873507.

It is not a weakly prime, because it can be changed into another prime (20873537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10436769 + 10436770.

It is an arithmetic number, because the mean of its divisors is an integer number (10436770).

Almost surely, 2^20873539 is an apocalyptic number.

20873539 is a deficient number, since it is larger than the sum of its proper divisors (1).

20873539 is an equidigital number, since it uses as much as digits as its factorization.

20873539 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 45360, while the sum is 37.

The square root of 20873539 is about 4568.7568331002. The cubic root of 20873539 is about 275.3374985772.

It can be divided in two parts, 20873 and 539, that added together give a palindrome (21412).

The spelling of 20873539 in words is "twenty million, eight hundred seventy-three thousand, five hundred thirty-nine".