1221121000111 has 4 divisors (see below), whose sum is σ = 1241139377224. Its totient is φ = 1201102623000.

The previous prime is 1221121000103. The next prime is 1221121000117. The reversal of 1221121000111 is 1110001211221.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1221121000111 - 2³ = 1221121000103 is a prime.

It is a super-2 number, since 2×1221121000111² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221121000091 and 1221121000100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221121000117) 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, 10009188465 + ... + 10009188586.

It is an arithmetic number, because the mean of its divisors is an integer number (310284844306).

Almost surely, 2^{1221121000111} is an apocalyptic number.

1221121000111 is a deficient number, since it is larger than the sum of its proper divisors (20018377113).

1221121000111 is an equidigital number, since it uses as much as digits as its factorization.

1221121000111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20018377112.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 1221121000111 its reverse (1110001211221), we get a palindrome (2331122211332).

The spelling of 1221121000111 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-one million, one hundred eleven", and thus it is an aban number.