1221240111 has 32 divisors (see below), whose sum is σ = 2026644480. Its totient is φ = 636920064.

The previous prime is 1221240109. The next prime is 1221240121. The reversal of 1221240111 is 1110421221.

It is not a de Polignac number, because 1221240111 - 2¹ = 1221240109 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221240121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 835 + ... + 49428.

It is an arithmetic number, because the mean of its divisors is an integer number (63332640).

Almost surely, 2^1221240111 is an apocalyptic number.

1221240111 is a deficient number, since it is larger than the sum of its proper divisors (805404369).

1221240111 is a wasteful number, since it uses less digits than its factorization.

1221240111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50375.

The product of its (nonzero) digits is 32, while the sum is 15.

The square root of 1221240111 is about 34946.2460215686. The cubic root of 1221240111 is about 1068.8916554893.

Adding to 1221240111 its reverse (1110421221), we get a palindrome (2331661332).

The spelling of 1221240111 in words is "one billion, two hundred twenty-one million, two hundred forty thousand, one hundred eleven".