20686339 has 4 divisors (see below), whose sum is σ = 20935656. Its totient is φ = 20437024.

The previous prime is 20686333. The next prime is 20686343. The reversal of 20686339 is 93368602.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20686339 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20686298 and 20686307.

It is not an unprimeable number, because it can be changed into a prime (20686333) 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, 124534 + ... + 124699.

It is an arithmetic number, because the mean of its divisors is an integer number (5233914).

Almost surely, 2^20686339 is an apocalyptic number.

20686339 is a deficient number, since it is larger than the sum of its proper divisors (249317).

20686339 is an equidigital number, since it uses as much as digits as its factorization.

20686339 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249316.

The product of its (nonzero) digits is 46656, while the sum is 37.

The square root of 20686339 is about 4548.2237192117. The cubic root of 20686339 is about 274.5119232426.

It can be divided in two parts, 20686 and 339, that added together give a square (21025 = 145²).

The spelling of 20686339 in words is "twenty million, six hundred eighty-six thousand, three hundred thirty-nine".