199129942978541 has 2 divisors, whose sum is σ = 199129942978542. Its totient is φ = 199129942978540.

The previous prime is 199129942978517. The next prime is 199129942978573. The reversal of 199129942978541 is 145879249921991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 197076393792100 + 2053549186441 = 14038390^2 + 1433021^2 .

It is an emirp because it is prime and its reverse (145879249921991) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199129942978541 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199129942971541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99564971489270 + 99564971489271.

It is an arithmetic number, because the mean of its divisors is an integer number (99564971489271).

Almost surely, 2^{199129942978541} is an apocalyptic number.

It is an amenable number.

199129942978541 is a deficient number, since it is larger than the sum of its proper divisors (1).

199129942978541 is an equidigital number, since it uses as much as digits as its factorization.

199129942978541 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1058158080, while the sum is 80.

The spelling of 199129942978541 in words is "one hundred ninety-nine trillion, one hundred twenty-nine billion, nine hundred forty-two million, nine hundred seventy-eight thousand, five hundred forty-one".