1221201018953 has 2 divisors, whose sum is σ = 1221201018954. Its totient is φ = 1221201018952.

The previous prime is 1221201018929. The next prime is 1221201018959. The reversal of 1221201018953 is 3598101021221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1094088804169 + 127112214784 = 1045987^2 + 356528^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221201018953 - 2²² = 1221196824649 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221201018959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610600509476 + 610600509477.

It is an arithmetic number, because the mean of its divisors is an integer number (610600509477).

Almost surely, 2^{1221201018953} is an apocalyptic number.

It is an amenable number.

1221201018953 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221201018953 is an equidigital number, since it uses as much as digits as its factorization.

1221201018953 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 35.

The spelling of 1221201018953 in words is "one trillion, two hundred twenty-one billion, two hundred one million, eighteen thousand, nine hundred fifty-three".