221865355 has 8 divisors (see below), whose sum is σ = 267090912. Its totient is φ = 176923968.

The previous prime is 221865353. The next prime is 221865359. The reversal of 221865355 is 553568122.

It is a happy number.

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 221865355 - 2¹ = 221865353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221865353) 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, 69319 + ... + 72448.

It is an arithmetic number, because the mean of its divisors is an integer number (33386364).

Almost surely, 2^221865355 is an apocalyptic number.

221865355 is a deficient number, since it is larger than the sum of its proper divisors (45225557).

221865355 is a wasteful number, since it uses less digits than its factorization.

221865355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142085.

The product of its digits is 72000, while the sum is 37.

The square root of 221865355 is about 14895.1453500797. The cubic root of 221865355 is about 605.3824551697.

The spelling of 221865355 in words is "two hundred twenty-one million, eight hundred sixty-five thousand, three hundred fifty-five".