204043621 has 4 divisors (see below), whose sum is σ = 204897600. Its totient is φ = 203189644.

The previous prime is 204043601. The next prime is 204043627. The reversal of 204043621 is 126340402.

It is a happy number.

204043621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 126340402 = 2 ⋅63170201.

It is a cyclic number.

It is not a de Polignac number, because 204043621 - 2²¹ = 201946469 is a prime.

It is a super-3 number, since 3×204043621³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 204043592 and 204043601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204043627) 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, 426631 + ... + 427108.

It is an arithmetic number, because the mean of its divisors is an integer number (51224400).

Almost surely, 2^204043621 is an apocalyptic number.

It is an amenable number.

204043621 is a deficient number, since it is larger than the sum of its proper divisors (853979).

204043621 is an equidigital number, since it uses as much as digits as its factorization.

204043621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 853978.

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 204043621 is about 14284.3838159019. The cubic root of 204043621 is about 588.7184872912.

It can be divided in two parts, 20404 and 3621, that added together give a square (24025 = 155²).

The spelling of 204043621 in words is "two hundred four million, forty-three thousand, six hundred twenty-one".