221365655 has 16 divisors (see below), whose sum is σ = 308121600. Its totient is φ = 149526432.

The previous prime is 221365631. The next prime is 221365657. The reversal of 221365655 is 556563122.

It is a cyclic number.

It is not a de Polignac number, because 221365655 - 2¹² = 221361559 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221365657) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44855 + ... + 49544.

It is an arithmetic number, because the mean of its divisors is an integer number (19257600).

Almost surely, 2^221365655 is an apocalyptic number.

221365655 is a deficient number, since it is larger than the sum of its proper divisors (86755945).

221365655 is an equidigital number, since it uses as much as digits as its factorization.

221365655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94478.

The product of its digits is 54000, while the sum is 35.

The square root of 221365655 is about 14878.3619730130. The cubic root of 221365655 is about 604.9276192352.

The spelling of 221365655 in words is "two hundred twenty-one million, three hundred sixty-five thousand, six hundred fifty-five".