20390206 has 8 divisors (see below), whose sum is σ = 31016304. Its totient is φ = 10051440.

The previous prime is 20390197. The next prime is 20390207. The reversal of 20390206 is 60209302.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20390207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71655 + ... + 71938.

It is an arithmetic number, because the mean of its divisors is an integer number (3877038).

Almost surely, 2^20390206 is an apocalyptic number.

20390206 is a deficient number, since it is larger than the sum of its proper divisors (10626098).

20390206 is a wasteful number, since it uses less digits than its factorization.

20390206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143666.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 20390206 is about 4515.5515720674. The cubic root of 20390206 is about 273.1957073697.

Adding to 20390206 its reverse (60209302), we get a palindrome (80599508).

It can be divided in two parts, 203 and 90206, that added together give a palindrome (90409).

The spelling of 20390206 in words is "twenty million, three hundred ninety thousand, two hundred six".