20684593 has 4 divisors (see below), whose sum is σ = 20816500. Its totient is φ = 20552688.

The previous prime is 20684581. The next prime is 20684611. The reversal of 20684593 is 39548602.

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

It can be written as a sum of positive squares in 2 ways, for example, as 5992704 + 14691889 = 2448^2 + 3833^2 .

It is a cyclic number.

It is not a de Polignac number, because 20684593 - 2⁵ = 20684561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20684693) 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, 65718 + ... + 66031.

It is an arithmetic number, because the mean of its divisors is an integer number (5204125).

Almost surely, 2^20684593 is an apocalyptic number.

It is an amenable number.

20684593 is a deficient number, since it is larger than the sum of its proper divisors (131907).

20684593 is a wasteful number, since it uses less digits than its factorization.

20684593 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131906.

The product of its (nonzero) digits is 51840, while the sum is 37.

The square root of 20684593 is about 4548.0317720966. The cubic root of 20684593 is about 274.5041997670.

The spelling of 20684593 in words is "twenty million, six hundred eighty-four thousand, five hundred ninety-three".