1221142210111 has 4 divisors (see below), whose sum is σ = 1230757503232. Its totient is φ = 1211526916992.

The previous prime is 1221142210073. The next prime is 1221142210153. The reversal of 1221142210111 is 1110122411221.

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-1221142210111 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221142210511) 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, 4807646370 + ... + 4807646623.

It is an arithmetic number, because the mean of its divisors is an integer number (307689375808).

Almost surely, 2^{1221142210111} is an apocalyptic number.

1221142210111 is a deficient number, since it is larger than the sum of its proper divisors (9615293121).

1221142210111 is an equidigital number, since it uses as much as digits as its factorization.

1221142210111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9615293120.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 1221142210111 its reverse (1110122411221), we get a palindrome (2331264621332).

The spelling of 1221142210111 in words is "one trillion, two hundred twenty-one billion, one hundred forty-two million, two hundred ten thousand, one hundred eleven".