18221198899433 has 2 divisors, whose sum is σ = 18221198899434. Its totient is φ = 18221198899432.

The previous prime is 18221198899427. The next prime is 18221198899451. The reversal of 18221198899433 is 33499889112281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14437286927449 + 3783911971984 = 3799643^2 + 1945228^2 .

It is a cyclic number.

It is not a de Polignac number, because 18221198899433 - 2⁴ = 18221198899417 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (18221198899633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9110599449716 + 9110599449717.

It is an arithmetic number, because the mean of its divisors is an integer number (9110599449717).

Almost surely, 2^{18221198899433} is an apocalyptic number.

It is an amenable number.

18221198899433 is a deficient number, since it is larger than the sum of its proper divisors (1).

18221198899433 is an equidigital number, since it uses as much as digits as its factorization.

18221198899433 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53747712, while the sum is 68.

The spelling of 18221198899433 in words is "eighteen trillion, two hundred twenty-one billion, one hundred ninety-eight million, eight hundred ninety-nine thousand, four hundred thirty-three".