1211220100121 has 8 divisors (see below), whose sum is σ = 1257262723080. Its totient is φ = 1165462571392.

The previous prime is 1211220100117. The next prime is 1211220100231. The reversal of 1211220100121 is 1210010221121.

It can be written as a sum of positive squares in 4 ways, for example, as 775535616025 + 435684484096 = 880645^2 + 660064^2 .

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 1211220100121 - 2² = 1211220100117 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1211220100096 and 1211220100105.

It is not an unprimeable number, because it can be changed into a prime (1211220100421) 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, 71264900 + ... + 71281893.

It is an arithmetic number, because the mean of its divisors is an integer number (157157840385).

Almost surely, 2^{1211220100121} is an apocalyptic number.

It is an amenable number.

1211220100121 is a deficient number, since it is larger than the sum of its proper divisors (46042622959).

1211220100121 is a wasteful number, since it uses less digits than its factorization.

1211220100121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142547115.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1211220100121 its reverse (1210010221121), we get a palindrome (2421230321242).

The spelling of 1211220100121 in words is "one trillion, two hundred eleven billion, two hundred twenty million, one hundred thousand, one hundred twenty-one".