11111112001221 has 8 divisors (see below), whose sum is σ = 14816316883584. Its totient is φ = 7406657559840.

The previous prime is 11111112001163. The next prime is 11111112001271. The reversal of 11111112001221 is 12210021111111.

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

It is not a de Polignac number, because 11111112001221 - 2²³ = 11111103612613 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11111112001221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11111112001271) 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, 187575696 + ... + 187634921.

It is an arithmetic number, because the mean of its divisors is an integer number (1852039610448).

Almost surely, 2^{11111112001221} is an apocalyptic number.

It is an amenable number.

11111112001221 is a deficient number, since it is larger than the sum of its proper divisors (3705204882363).

11111112001221 is an equidigital number, since it uses as much as digits as its factorization.

11111112001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375220491.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 11111112001221 its reverse (12210021111111), we get a palindrome (23321133112332).

The spelling of 11111112001221 in words is "eleven trillion, one hundred eleven billion, one hundred twelve million, one thousand, two hundred twenty-one".