221634413 has 16 divisors (see below), whose sum is σ = 297580416. Its totient is φ = 159416640.

The previous prime is 221634383. The next prime is 221634419. The reversal of 221634413 is 314436122.

It is a cyclic number.

It is not a de Polignac number, because 221634413 - 2¹⁰ = 221633389 is a prime.

It is a Smith number, since the sum of its digits (26) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221634419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 109706 + ... + 111707.

It is an arithmetic number, because the mean of its divisors is an integer number (18598776).

Almost surely, 2^221634413 is an apocalyptic number.

It is an amenable number.

221634413 is a deficient number, since it is larger than the sum of its proper divisors (75946003).

221634413 is a wasteful number, since it uses less digits than its factorization.

221634413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221444.

The product of its digits is 3456, while the sum is 26.

The square root of 221634413 is about 14887.3910743286. The cubic root of 221634413 is about 605.1723325748.

The spelling of 221634413 in words is "two hundred twenty-one million, six hundred thirty-four thousand, four hundred thirteen".