1001221101021 has 4 divisors (see below), whose sum is σ = 1334961468032. Its totient is φ = 667480734012.

The previous prime is 1001221100987. The next prime is 1001221101047. The reversal of 1001221101021 is 1201011221001.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1001221101021 - 2¹⁰ = 1001221099997 is a prime.

It is a super-3 number, since 3×1001221101021³ (a number of 37 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1001221100988 and 1001221101006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001221111021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 166870183501 + ... + 166870183506.

It is an arithmetic number, because the mean of its divisors is an integer number (333740367008).

Almost surely, 2^{1001221101021} is an apocalyptic number.

It is an amenable number.

1001221101021 is a deficient number, since it is larger than the sum of its proper divisors (333740367011).

1001221101021 is an equidigital number, since it uses as much as digits as its factorization.

1001221101021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333740367010.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 1001221101021 its reverse (1201011221001), we get a palindrome (2202232322022).

The spelling of 1001221101021 in words is "one trillion, one billion, two hundred twenty-one million, one hundred one thousand, twenty-one".