1001111212221 has 8 divisors (see below), whose sum is σ = 1338533098560. Its totient is φ = 665548400352.

The previous prime is 1001111212217. The next prime is 1001111212247. The reversal of 1001111212221 is 1222121111001.

It is a happy number.

1001111212221 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 1001111212221 - 2² = 1001111212217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1001111212221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001111212021) 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, 464767360 + ... + 464769513.

It is an arithmetic number, because the mean of its divisors is an integer number (167316637320).

Almost surely, 2^{1001111212221} is an apocalyptic number.

It is an amenable number.

1001111212221 is a deficient number, since it is larger than the sum of its proper divisors (337421886339).

1001111212221 is an equidigital number, since it uses as much as digits as its factorization.

1001111212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 929537235.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1001111212221 its reverse (1222121111001), we get a palindrome (2223232323222).

The spelling of 1001111212221 in words is "one trillion, one billion, one hundred eleven million, two hundred twelve thousand, two hundred twenty-one".