221002109 has 4 divisors (see below), whose sum is σ = 222689280. Its totient is φ = 219314940.

The previous prime is 221002097. The next prime is 221002121. The reversal of 221002109 is 901200122.

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.

It is an interprime number because it is at equal distance from previous prime (221002097) and next prime (221002121).

It is a cyclic number.

It is not a de Polignac number, because 221002109 - 2²⁰ = 219953533 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221002169) 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, 843389 + ... + 843650.

It is an arithmetic number, because the mean of its divisors is an integer number (55672320).

Almost surely, 2^221002109 is an apocalyptic number.

It is an amenable number.

221002109 is a deficient number, since it is larger than the sum of its proper divisors (1687171).

221002109 is a wasteful number, since it uses less digits than its factorization.

221002109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1687170.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 221002109 is about 14866.1396804954. The cubic root of 221002109 is about 604.5962828071.

The spelling of 221002109 in words is "two hundred twenty-one million, two thousand, one hundred nine".