1221001110253 has 2 divisors, whose sum is σ = 1221001110254. Its totient is φ = 1221001110252.

The previous prime is 1221001110181. The next prime is 1221001110389. The reversal of 1221001110253 is 3520111001221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1185742410724 + 35258699529 = 1088918^2 + 187773^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221001110253 - 2¹⁷ = 1221000979181 is a prime.

It is a super-2 number, since 2×1221001110253² (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 1221001110253.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221001180253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610500555126 + 610500555127.

It is an arithmetic number, because the mean of its divisors is an integer number (610500555127).

Almost surely, 2^{1221001110253} is an apocalyptic number.

It is an amenable number.

1221001110253 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221001110253 is an equidigital number, since it uses as much as digits as its factorization.

1221001110253 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 1221001110253 its reverse (3520111001221), we get a palindrome (4741112111474).

The spelling of 1221001110253 in words is "one trillion, two hundred twenty-one billion, one million, one hundred ten thousand, two hundred fifty-three".