1211222001091 has 4 divisors (see below), whose sum is σ = 1211243795632. Its totient is φ = 1211200206552.

The previous prime is 1211222001061. The next prime is 1211222001113. The reversal of 1211222001091 is 1901002221121.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1211222001091 is a prime.

It is a super-3 number, since 3×1211222001091³ (a number of 37 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1211222001061) 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, 10813695 + ... + 10925128.

It is an arithmetic number, because the mean of its divisors is an integer number (302810948908).

Almost surely, 2^{1211222001091} is an apocalyptic number.

1211222001091 is a deficient number, since it is larger than the sum of its proper divisors (21794541).

1211222001091 is an equidigital number, since it uses as much as digits as its factorization.

1211222001091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21794540.

The product of its (nonzero) digits is 144, while the sum is 22.

The spelling of 1211222001091 in words is "one trillion, two hundred eleven billion, two hundred twenty-two million, one thousand, ninety-one".