1001221220121 has 8 divisors (see below), whose sum is σ = 1334975568000. Its totient is φ = 667473842832.

The previous prime is 1001221220107. The next prime is 1001221220123. The reversal of 1001221220121 is 1210221221001.

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

It is not a de Polignac number, because 1001221220121 - 2⁵ = 1001221220089 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1001221220121.

It is not an unprimeable number, because it can be changed into a prime (1001221220123) 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, 1397746 + ... + 1989003.

It is an arithmetic number, because the mean of its divisors is an integer number (166871946000).

Almost surely, 2^{1001221220121} is an apocalyptic number.

It is an amenable number.

1001221220121 is a deficient number, since it is larger than the sum of its proper divisors (333754347879).

1001221220121 is an equidigital number, since it uses as much as digits as its factorization.

1001221220121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3485295.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 1001221220121 its reverse (1210221221001), we get a palindrome (2211442441122).

The spelling of 1001221220121 in words is "one trillion, one billion, two hundred twenty-one million, two hundred twenty thousand, one hundred twenty-one".