20046643 has 4 divisors (see below), whose sum is σ = 20512888. Its totient is φ = 19580400.

The previous prime is 20046619. The next prime is 20046659. The reversal of 20046643 is 34664002.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34664002 = 2 ⋅17332001.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20046643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20016643) 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, 233058 + ... + 233143.

It is an arithmetic number, because the mean of its divisors is an integer number (5128222).

Almost surely, 2^20046643 is an apocalyptic number.

20046643 is a deficient number, since it is larger than the sum of its proper divisors (466245).

20046643 is an equidigital number, since it uses as much as digits as its factorization.

20046643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 466244.

The product of its (nonzero) digits is 3456, while the sum is 25.

The square root of 20046643 is about 4477.3477640228. The cubic root of 20046643 is about 271.6526121342.

The spelling of 20046643 in words is "twenty million, forty-six thousand, six hundred forty-three".