221000323121 has 4 divisors (see below), whose sum is σ = 221034598500. Its totient is φ = 220966047744.

The previous prime is 221000323073. The next prime is 221000323129. The reversal of 221000323121 is 121323000122.

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

It can be written as a sum of positive squares in 2 ways, for example, as 156270786721 + 64729536400 = 395311^2 + 254420^2 .

It is a cyclic number.

It is not a de Polignac number, because 221000323121 - 2⁶ = 221000323057 is a prime.

It is a super-2 number, since 2×221000323121² (a number of 23 digits) contains 22 as substring.

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 221000323121.

It is not an unprimeable number, because it can be changed into a prime (221000323129) 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, 17128016 + ... + 17140913.

It is an arithmetic number, because the mean of its divisors is an integer number (55258649625).

Almost surely, 2^221000323121 is an apocalyptic number.

It is an amenable number.

221000323121 is a deficient number, since it is larger than the sum of its proper divisors (34275379).

221000323121 is an equidigital number, since it uses as much as digits as its factorization.

221000323121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34275378.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 221000323121 its reverse (121323000122), we get a palindrome (342323323243).

The spelling of 221000323121 in words is "two hundred twenty-one billion, three hundred twenty-three thousand, one hundred twenty-one".