1221201010111 has 8 divisors (see below), whose sum is σ = 1263868719120. Its totient is φ = 1178570456448.

The previous prime is 1221201010097. The next prime is 1221201010123. The reversal of 1221201010111 is 1110101021221.

It is a happy number.

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 1221201010111 - 2⁷ = 1221201009983 is a prime.

It is a super-2 number, since 2×1221201010111² (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 = 1221201010091 and 1221201010100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221201010181) 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, 9221946 + ... + 9353431.

It is an arithmetic number, because the mean of its divisors is an integer number (157983589890).

Almost surely, 2^{1221201010111} is an apocalyptic number.

1221201010111 is a deficient number, since it is larger than the sum of its proper divisors (42667709009).

1221201010111 is a wasteful number, since it uses less digits than its factorization.

1221201010111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18577673.

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

Adding to 1221201010111 its reverse (1110101021221), we get a palindrome (2331302031332).

The spelling of 1221201010111 in words is "one trillion, two hundred twenty-one billion, two hundred one million, ten thousand, one hundred eleven".