221005552121 has 8 divisors (see below), whose sum is σ = 221376195144. Its totient is φ = 220635129600.

The previous prime is 221005552109. The next prime is 221005552133. The reversal of 221005552121 is 121255500122.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (221005552109) and next prime (221005552133).

It can be written as a sum of positive squares in 4 ways, for example, as 28779426025 + 192226126096 = 169645^2 + 438436^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221005552121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221005552151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2015921 + ... + 2122721.

It is an arithmetic number, because the mean of its divisors is an integer number (27672024393).

Almost surely, 2^221005552121 is an apocalyptic number.

It is an amenable number.

221005552121 is a deficient number, since it is larger than the sum of its proper divisors (370643023).

221005552121 is a wasteful number, since it uses less digits than its factorization.

221005552121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110251.

The product of its (nonzero) digits is 2000, while the sum is 26.

The spelling of 221005552121 in words is "two hundred twenty-one billion, five million, five hundred fifty-two thousand, one hundred twenty-one".