199981248497 has 2 divisors, whose sum is σ = 199981248498. Its totient is φ = 199981248496.

The previous prime is 199981248421. The next prime is 199981248557. The reversal of 199981248497 is 794842189991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 172145329216 + 27835919281 = 414904^2 + 166841^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199981248497 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 199981248497.

It is not a weakly prime, because it can be changed into another prime (199981248407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99990624248 + 99990624249.

It is an arithmetic number, because the mean of its divisors is an integer number (99990624249).

Almost surely, 2^199981248497 is an apocalyptic number.

It is an amenable number.

199981248497 is a deficient number, since it is larger than the sum of its proper divisors (1).

199981248497 is an equidigital number, since it uses as much as digits as its factorization.

199981248497 is an evil number, because the sum of its binary digits is even.

The product of its digits is 94058496, while the sum is 71.

The spelling of 199981248497 in words is "one hundred ninety-nine billion, nine hundred eighty-one million, two hundred forty-eight thousand, four hundred ninety-seven".