220121543 has 4 divisors (see below), whose sum is σ = 220356408. Its totient is φ = 219886680.

The previous prime is 220121519. The next prime is 220121549. The reversal of 220121543 is 345121022.

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 220121543 - 2¹⁸ = 219859399 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 (220121549) 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, 116021 + ... + 117902.

It is an arithmetic number, because the mean of its divisors is an integer number (55089102).

Almost surely, 2^220121543 is an apocalyptic number.

220121543 is a deficient number, since it is larger than the sum of its proper divisors (234865).

220121543 is an equidigital number, since it uses as much as digits as its factorization.

220121543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234864.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 220121543 is about 14836.4936221467. The cubic root of 220121543 is about 603.7922247415.

Adding to 220121543 its reverse (345121022), we get a palindrome (565242565).

The spelling of 220121543 in words is "two hundred twenty million, one hundred twenty-one thousand, five hundred forty-three".