1225191921361 has 2 divisors, whose sum is σ = 1225191921362. Its totient is φ = 1225191921360.

The previous prime is 1225191921353. The next prime is 1225191921461. The reversal of 1225191921361 is 1631291915221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1157991210000 + 67200711361 = 1076100^2 + 259231^2 .

It is an emirp because it is prime and its reverse (1631291915221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1225191921361 - 2³ = 1225191921353 is a prime.

It is not a weakly prime, because it can be changed into another prime (1225191921461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 612595960680 + 612595960681.

It is an arithmetic number, because the mean of its divisors is an integer number (612595960681).

Almost surely, 2^{1225191921361} is an apocalyptic number.

It is an amenable number.

1225191921361 is a deficient number, since it is larger than the sum of its proper divisors (1).

1225191921361 is an equidigital number, since it uses as much as digits as its factorization.

1225191921361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 58320, while the sum is 43.

The spelling of 1225191921361 in words is "one trillion, two hundred twenty-five billion, one hundred ninety-one million, nine hundred twenty-one thousand, three hundred sixty-one".