221277221 has 8 divisors (see below), whose sum is σ = 249717600. Its totient is φ = 194224240.

The previous prime is 221277197. The next prime is 221277241. The reversal of 221277221 is 122772122.

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

It is a cyclic number.

It is not a de Polignac number, because 221277221 - 2¹⁰ = 221276197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221277241) 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, 346511 + ... + 347148.

It is an arithmetic number, because the mean of its divisors is an integer number (31214700).

Almost surely, 2^221277221 is an apocalyptic number.

It is an amenable number.

221277221 is a deficient number, since it is larger than the sum of its proper divisors (28440379).

221277221 is a wasteful number, since it uses less digits than its factorization.

221277221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 693699.

The product of its digits is 1568, while the sum is 26.

The square root of 221277221 is about 14875.3897764059. The cubic root of 221277221 is about 604.8470537496.

The spelling of 221277221 in words is "two hundred twenty-one million, two hundred seventy-seven thousand, two hundred twenty-one".