1221112221893 has 2 divisors, whose sum is σ = 1221112221894. Its totient is φ = 1221112221892.

The previous prime is 1221112221881. The next prime is 1221112221899. The reversal of 1221112221893 is 3981222111221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 751451460769 + 469660761124 = 866863^2 + 685318^2 .

It is an emirp because it is prime and its reverse (3981222111221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1221112221893 - 2⁴ = 1221112221877 is a prime.

It is a super-2 number, since 2×1221112221893² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221112221899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610556110946 + 610556110947.

It is an arithmetic number, because the mean of its divisors is an integer number (610556110947).

Almost surely, 2^{1221112221893} is an apocalyptic number.

It is an amenable number.

1221112221893 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221112221893 is an equidigital number, since it uses as much as digits as its factorization.

1221112221893 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6912, while the sum is 35.

The spelling of 1221112221893 in words is "one trillion, two hundred twenty-one billion, one hundred twelve million, two hundred twenty-one thousand, eight hundred ninety-three".