20549143 has 4 divisors (see below), whose sum is σ = 21442608. Its totient is φ = 19655680.

The previous prime is 20549071. The next prime is 20549153. The reversal of 20549143 is 34194502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34194502 = 2 ⋅17097251.

It is a cyclic number.

It is not a de Polignac number, because 20549143 - 2¹³ = 20540951 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 (20549153) 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, 446698 + ... + 446743.

It is an arithmetic number, because the mean of its divisors is an integer number (5360652).

Almost surely, 2^20549143 is an apocalyptic number.

20549143 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

20549143 is a deficient number, since it is larger than the sum of its proper divisors (893465).

20549143 is an equidigital number, since it uses as much as digits as its factorization.

20549143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 893464.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 20549143 is about 4533.1162570576. The cubic root of 20549143 is about 273.9037037069.

The spelling of 20549143 in words is "twenty million, five hundred forty-nine thousand, one hundred forty-three".