11211220120985 has 4 divisors (see below), whose sum is σ = 13453464145188. Its totient is φ = 8968976096784.

The previous prime is 11211220120901. The next prime is 11211220120987. The reversal of 11211220120985 is 58902102211211.

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 3135552021001 + 8075668099984 = 1770749^2 + 2841772^2 .

It is a cyclic number.

It is not a de Polignac number, because 11211220120985 - 2¹⁶ = 11211220055449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11211220120987) 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, 1121122012094 + ... + 1121122012103.

It is an arithmetic number, because the mean of its divisors is an integer number (3363366036297).

Almost surely, 2^{11211220120985} is an apocalyptic number.

It is an amenable number.

11211220120985 is a deficient number, since it is larger than the sum of its proper divisors (2242244024203).

11211220120985 is an equidigital number, since it uses as much as digits as its factorization.

11211220120985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2242244024202.

The product of its (nonzero) digits is 5760, while the sum is 35.

The spelling of 11211220120985 in words is "eleven trillion, two hundred eleven billion, two hundred twenty million, one hundred twenty thousand, nine hundred eighty-five".