1221110001253 has 2 divisors, whose sum is σ = 1221110001254. Its totient is φ = 1221110001252.

The previous prime is 1221110001197. The next prime is 1221110001263. The reversal of 1221110001253 is 3521000111221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 965359305729 + 255750695524 = 982527^2 + 505718^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221110001253 is a prime.

It is a super-2 number, since 2×1221110001253² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1221110001253.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221110001263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610555000626 + 610555000627.

It is an arithmetic number, because the mean of its divisors is an integer number (610555000627).

Almost surely, 2^{1221110001253} is an apocalyptic number.

It is an amenable number.

1221110001253 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221110001253 is an equidigital number, since it uses as much as digits as its factorization.

1221110001253 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120, while the sum is 19.

Adding to 1221110001253 its reverse (3521000111221), we get a palindrome (4742110112474).

The spelling of 1221110001253 in words is "one trillion, two hundred twenty-one billion, one hundred ten million, one thousand, two hundred fifty-three".