221085655 has 16 divisors (see below), whose sum is σ = 308176704. Its totient is φ = 149114880.

The previous prime is 221085649. The next prime is 221085659. The reversal of 221085655 is 556580122.

It is a de Polignac number, because none of the positive numbers 2^k-221085655 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221085655.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221085659) 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, 49642 + ... + 53911.

It is an arithmetic number, because the mean of its divisors is an integer number (19261044).

Almost surely, 2^221085655 is an apocalyptic number.

221085655 is a deficient number, since it is larger than the sum of its proper divisors (87091049).

221085655 is a wasteful number, since it uses less digits than its factorization.

221085655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103626.

The product of its (nonzero) digits is 24000, while the sum is 34.

The square root of 221085655 is about 14868.9493576379. The cubic root of 221085655 is about 604.6724589087.

The spelling of 221085655 in words is "two hundred twenty-one million, eighty-five thousand, six hundred fifty-five".