1221154105201 has 2 divisors, whose sum is σ = 1221154105202. Its totient is φ = 1221154105200.

The previous prime is 1221154105159. The next prime is 1221154105271. The reversal of 1221154105201 is 1025014511221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1080510354576 + 140643750625 = 1039476^2 + 375025^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221154105201 - 2¹⁵ = 1221154072433 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221154105271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610577052600 + 610577052601.

It is an arithmetic number, because the mean of its divisors is an integer number (610577052601).

Almost surely, 2^{1221154105201} is an apocalyptic number.

It is an amenable number.

1221154105201 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221154105201 is an equidigital number, since it uses as much as digits as its factorization.

1221154105201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 800, while the sum is 25.

Adding to 1221154105201 its reverse (1025014511221), we get a palindrome (2246168616422).

The spelling of 1221154105201 in words is "one trillion, two hundred twenty-one billion, one hundred fifty-four million, one hundred five thousand, two hundred one".