1221111100121 has 8 divisors (see below), whose sum is σ = 1410481270944. Its totient is φ = 1044800941120.

The previous prime is 1221111100117. The next prime is 1221111100129. The reversal of 1221111100121 is 1210011111221.

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 1221111100121 - 2² = 1221111100117 is a prime.

It is a super-2 number, since 2×1221111100121² (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 = 1221111100096 and 1221111100105.

It is not an unprimeable number, because it can be changed into a prime (1221111100129) 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, 3265002755 + ... + 3265003128.

It is an arithmetic number, because the mean of its divisors is an integer number (176310158868).

Almost surely, 2^{1221111100121} is an apocalyptic number.

1221111100121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221111100121 is a deficient number, since it is larger than the sum of its proper divisors (189370170823).

1221111100121 is a wasteful number, since it uses less digits than its factorization.

1221111100121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6530005911.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 1221111100121 its reverse (1210011111221), we get a palindrome (2431122211342).

It can be divided in two parts, 1221111100 and 121, that added together give a palindrome (1221111221).

The spelling of 1221111100121 in words is "one trillion, two hundred twenty-one billion, one hundred eleven million, one hundred thousand, one hundred twenty-one".