18643896228149 has 2 divisors, whose sum is σ = 18643896228150. Its totient is φ = 18643896228148.

The previous prime is 18643896228137. The next prime is 18643896228229. The reversal of 18643896228149 is 94182269834681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16616140164100 + 2027756064049 = 4076290^2 + 1423993^2 .

It is a cyclic number.

It is not a de Polignac number, because 18643896228149 - 2¹² = 18643896224053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18643896228109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9321948114074 + 9321948114075.

It is an arithmetic number, because the mean of its divisors is an integer number (9321948114075).

Almost surely, 2^{18643896228149} is an apocalyptic number.

It is an amenable number.

18643896228149 is a deficient number, since it is larger than the sum of its proper divisors (1).

18643896228149 is an equidigital number, since it uses as much as digits as its factorization.

18643896228149 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 286654464, while the sum is 71.

The spelling of 18643896228149 in words is "eighteen trillion, six hundred forty-three billion, eight hundred ninety-six million, two hundred twenty-eight thousand, one hundred forty-nine".