20644286 has 8 divisors (see below), whose sum is σ = 33348504. Its totient is φ = 9528120.

The previous prime is 20644237. The next prime is 20644303. The reversal of 20644286 is 68244602.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

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, 396980 + ... + 397031.

It is an arithmetic number, because the mean of its divisors is an integer number (4168563).

Almost surely, 2^20644286 is an apocalyptic number.

20644286 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

20644286 is a deficient number, since it is larger than the sum of its proper divisors (12704218).

20644286 is a wasteful number, since it uses less digits than its factorization.

20644286 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 794026.

The product of its (nonzero) digits is 18432, while the sum is 32.

The square root of 20644286 is about 4543.5983537280. The cubic root of 20644286 is about 274.3257797634.

Adding to 20644286 its reverse (68244602), we get a palindrome (88888888).

The spelling of 20644286 in words is "twenty million, six hundred forty-four thousand, two hundred eighty-six".