16181972154433 has 2 divisors, whose sum is σ = 16181972154434. Its totient is φ = 16181972154432.

The previous prime is 16181972154431. The next prime is 16181972154521. The reversal of 16181972154433 is 33445127918161.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8264406044944 + 7917566109489 = 2874788^2 + 2813817^2 .

It is an emirp because it is prime and its reverse (33445127918161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16181972154433 - 2¹ = 16181972154431 is a prime.

Together with 16181972154431, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (16181972154431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8090986077216 + 8090986077217.

It is an arithmetic number, because the mean of its divisors is an integer number (8090986077217).

Almost surely, 2^{16181972154433} is an apocalyptic number.

It is an amenable number.

16181972154433 is a deficient number, since it is larger than the sum of its proper divisors (1).

16181972154433 is an equidigital number, since it uses as much as digits as its factorization.

16181972154433 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4354560, while the sum is 55.

The spelling of 16181972154433 in words is "sixteen trillion, one hundred eighty-one billion, nine hundred seventy-two million, one hundred fifty-four thousand, four hundred thirty-three".