221645043 has 24 divisors (see below), whose sum is σ = 337229568. Its totient is φ = 140003952.

The previous prime is 221645027. The next prime is 221645077. The reversal of 221645043 is 340546122.

221645043 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221645043 - 2⁴ = 221645027 is a prime.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 221644998 and 221645016.

It is not an unprimeable number, because it can be changed into a prime (221645023) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17146 + ... + 27152.

It is an arithmetic number, because the mean of its divisors is an integer number (14051232).

Almost surely, 2^221645043 is an apocalyptic number.

221645043 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

221645043 is a deficient number, since it is larger than the sum of its proper divisors (115584525).

221645043 is a wasteful number, since it uses less digits than its factorization.

221645043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10143 (or 10140 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 221645043 is about 14887.7480835753. The cubic root of 221645043 is about 605.1820074849.

The spelling of 221645043 in words is "two hundred twenty-one million, six hundred forty-five thousand, forty-three".