20447143 has 4 divisors (see below), whose sum is σ = 20457448. Its totient is φ = 20436840.

The previous prime is 20447131. The next prime is 20447159. The reversal of 20447143 is 34174402.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20447143 - 2⁵ = 20447111 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20447183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1128 + ... + 6493.

It is an arithmetic number, because the mean of its divisors is an integer number (5114362).

Almost surely, 2^20447143 is an apocalyptic number.

20447143 is a deficient number, since it is larger than the sum of its proper divisors (10305).

20447143 is an equidigital number, since it uses as much as digits as its factorization.

20447143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10304.

The product of its (nonzero) digits is 2688, while the sum is 25.

The square root of 20447143 is about 4521.8517224695. The cubic root of 20447143 is about 273.4497588822.

The spelling of 20447143 in words is "twenty million, four hundred forty-seven thousand, one hundred forty-three".