221364009 has 24 divisors (see below), whose sum is σ = 332305792. Its totient is φ = 147258000.

The previous prime is 221364001. The next prime is 221364097. The reversal of 221364009 is 900463122.

221364009 is a `hidden beast` number, since 2 + 2 + 13 + 640 + 0 + 9 = 666.

It is not a de Polignac number, because 221364009 - 2³ = 221364001 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221364001) 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, 181887 + ... + 183099.

Almost surely, 2^221364009 is an apocalyptic number.

It is an amenable number.

221364009 is a deficient number, since it is larger than the sum of its proper divisors (110941783).

221364009 is an equidigital number, since it uses as much as digits as its factorization.

221364009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1979 (or 1967 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 221364009 is about 14878.3066576812. The cubic root of 221364009 is about 604.9261198858.

The spelling of 221364009 in words is "two hundred twenty-one million, three hundred sixty-four thousand, nine".