1001011221221 has 8 divisors (see below), whose sum is σ = 1156248255744. Its totient is φ = 856480189120.

The previous prime is 1001011221209. The next prime is 1001011221229. The reversal of 1001011221221 is 1221221101001.

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

It is a cyclic number.

It is not a de Polignac number, because 1001011221221 - 2¹⁸ = 1001010959077 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1001011221196 and 1001011221205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001011221229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2676500405 + ... + 2676500778.

It is an arithmetic number, because the mean of its divisors is an integer number (144531031968).

Almost surely, 2^{1001011221221} is an apocalyptic number.

1001011221221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1001011221221 is a deficient number, since it is larger than the sum of its proper divisors (155237034523).

1001011221221 is a wasteful number, since it uses less digits than its factorization.

1001011221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5353001211.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1001011221221 its reverse (1221221101001), we get a palindrome (2222232322222).

The spelling of 1001011221221 in words is "one trillion, one billion, eleven million, two hundred twenty-one thousand, two hundred twenty-one".