221886021 has 8 divisors (see below), whose sum is σ = 338112064. Its totient is φ = 126792000.

The previous prime is 221886011. The next prime is 221886029. The reversal of 221886021 is 120688122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 221886021 - 2⁹ = 221885509 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221886021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221886029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5282980 + ... + 5283021.

It is an arithmetic number, because the mean of its divisors is an integer number (42264008).

Almost surely, 2^221886021 is an apocalyptic number.

221886021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

221886021 is a deficient number, since it is larger than the sum of its proper divisors (116226043).

221886021 is a wasteful number, since it uses less digits than its factorization.

221886021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10566011.

The product of its (nonzero) digits is 3072, while the sum is 30.

The square root of 221886021 is about 14895.8390498824. The cubic root of 221886021 is about 605.4012510221.

The spelling of 221886021 in words is "two hundred twenty-one million, eight hundred eighty-six thousand, twenty-one".