221042135 has 4 divisors (see below), whose sum is σ = 265250568. Its totient is φ = 176833704.

The previous prime is 221042119. The next prime is 221042137. The reversal of 221042135 is 531240122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 221042135 - 2⁴ = 221042119 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221042137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22104209 + ... + 22104218.

It is an arithmetic number, because the mean of its divisors is an integer number (66312642).

Almost surely, 2^221042135 is an apocalyptic number.

221042135 is a deficient number, since it is larger than the sum of its proper divisors (44208433).

221042135 is an equidigital number, since it uses as much as digits as its factorization.

221042135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44208432.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 221042135 is about 14867.4858331865. The cubic root of 221042135 is about 604.6327803623.

Adding to 221042135 its reverse (531240122), we get a palindrome (752282257).

The spelling of 221042135 in words is "two hundred twenty-one million, forty-two thousand, one hundred thirty-five".