1221022221111 has 144 divisors (see below), whose sum is σ = 2361735118080. Its totient is φ = 599897168640.

The previous prime is 1221022221091. The next prime is 1221022221131. The reversal of 1221022221111 is 1111222201221.

1221022221111 is a `hidden beast` number, since 1 + 221 + 0 + 222 + 211 + 11 = 666.

It is an interprime number because it is at equal distance from previous prime (1221022221091) and next prime (1221022221131).

It is not a de Polignac number, because 1221022221111 - 2⁵ = 1221022221079 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221022221131) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 9868516 + ... + 9991478.

It is an arithmetic number, because the mean of its divisors is an integer number (16400938320).

Almost surely, 2^{1221022221111} is an apocalyptic number.

1221022221111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1221022221111 is a deficient number, since it is larger than the sum of its proper divisors (1140712896969).

1221022221111 is a wasteful number, since it uses less digits than its factorization.

1221022221111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123106 (or 123096 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 1221022221111 its reverse (1111222201221), we get a palindrome (2332244422332).

The spelling of 1221022221111 in words is "one trillion, two hundred twenty-one billion, twenty-two million, two hundred twenty-one thousand, one hundred eleven".