20806193 has 4 divisors (see below), whose sum is σ = 20885568. Its totient is φ = 20726820.

The previous prime is 20806189. The next prime is 20806199. The reversal of 20806193 is 39160802.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 39160802 = 2 ⋅19580401.

It is a cyclic number.

It is not a de Polignac number, because 20806193 - 2² = 20806189 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20806199) 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, 39293 + ... + 39818.

It is an arithmetic number, because the mean of its divisors is an integer number (5221392).

Almost surely, 2^20806193 is an apocalyptic number.

It is an amenable number.

20806193 is a deficient number, since it is larger than the sum of its proper divisors (79375).

20806193 is an equidigital number, since it uses as much as digits as its factorization.

20806193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79374.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 20806193 is about 4561.3806024054. The cubic root of 20806193 is about 275.0410649420.

Adding to 20806193 its reverse (39160802), we get a palindrome (59966995).

The spelling of 20806193 in words is "twenty million, eight hundred six thousand, one hundred ninety-three".