1001100122221 has 8 divisors (see below), whose sum is σ = 1010019698424. Its totient is φ = 992181603840.

The previous prime is 1001100122173. The next prime is 1001100122251. The reversal of 1001100122221 is 1222210011001.

It can be written as a sum of positive squares in 4 ways, for example, as 80095226121 + 921004896100 = 283011^2 + 959690^2 .

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 1001100122221 - 2¹⁹ = 1001099597933 is a prime.

It is a super-2 number, since 2×1001100122221² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001100122251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1701535 + ... + 2213011.

It is an arithmetic number, because the mean of its divisors is an integer number (126252462303).

Almost surely, 2^{1001100122221} is an apocalyptic number.

It is an amenable number.

1001100122221 is a deficient number, since it is larger than the sum of its proper divisors (8919576203).

1001100122221 is a wasteful number, since it uses less digits than its factorization.

1001100122221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 528911.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 1001100122221 its reverse (1222210011001), we get a palindrome (2223310133222).

The spelling of 1001100122221 in words is "one trillion, one billion, one hundred million, one hundred twenty-two thousand, two hundred twenty-one".