1221121012201 has 4 divisors (see below), whose sum is σ = 1221125624404. Its totient is φ = 1221116400000.

The previous prime is 1221121012193. The next prime is 1221121012217. The reversal of 1221121012201 is 1022101211221.

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

It can be written as a sum of positive squares in 2 ways, for example, as 225468277225 + 995652734976 = 474835^2 + 997824^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221121012201 - 2³ = 1221121012193 is a prime.

It is a super-2 number, since 2×1221121012201² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221121012301) 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, 1883100 + ... + 2447101.

It is an arithmetic number, because the mean of its divisors is an integer number (305281406101).

Almost surely, 2^{1221121012201} is an apocalyptic number.

It is an amenable number.

1221121012201 is a deficient number, since it is larger than the sum of its proper divisors (4612203).

1221121012201 is an equidigital number, since it uses as much as digits as its factorization.

1221121012201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4612202.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1221121012201 its reverse (1022101211221), we get a palindrome (2243222223422).

The spelling of 1221121012201 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-one million, twelve thousand, two hundred one".