20555543 has 4 divisors (see below), whose sum is σ = 20614128. Its totient is φ = 20496960.

The previous prime is 20555527. The next prime is 20555551. The reversal of 20555543 is 34555502.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20555543 - 2⁴ = 20555527 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 (20555503) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28763 + ... + 29468.

It is an arithmetic number, because the mean of its divisors is an integer number (5153532).

Almost surely, 2^20555543 is an apocalyptic number.

20555543 is a deficient number, since it is larger than the sum of its proper divisors (58585).

20555543 is an equidigital number, since it uses as much as digits as its factorization.

20555543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58584.

The product of its (nonzero) digits is 15000, while the sum is 29.

The square root of 20555543 is about 4533.8221182574. The cubic root of 20555543 is about 273.9321363890.

The spelling of 20555543 in words is "twenty million, five hundred fifty-five thousand, five hundred forty-three".