221440999 has 4 divisors (see below), whose sum is σ = 238474936. Its totient is φ = 204407064.

The previous prime is 221440981. The next prime is 221441053. The reversal of 221440999 is 999044122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 221440999 - 2¹⁹ = 220916711 is a prime.

It is a super-2 number, since 2×221440999² = 98072232076236002, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221440979) 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, 8516949 + ... + 8516974.

It is an arithmetic number, because the mean of its divisors is an integer number (59618734).

Almost surely, 2^221440999 is an apocalyptic number.

221440999 is a deficient number, since it is larger than the sum of its proper divisors (17033937).

221440999 is a wasteful number, since it uses less digits than its factorization.

221440999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17033936.

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 221440999 is about 14880.8937567607. The cubic root of 221440999 is about 604.9962424920.

The spelling of 221440999 in words is "two hundred twenty-one million, four hundred forty thousand, nine hundred ninety-nine".