19871191037 has 2 divisors, whose sum is σ = 19871191038. Its totient is φ = 19871191036.

The previous prime is 19871191031. The next prime is 19871191069. The reversal of 19871191037 is 73019117891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19393069081 + 478121956 = 139259^2 + 21866^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19871191037 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 19871190982 and 19871191000.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19871191031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9935595518 + 9935595519.

It is an arithmetic number, because the mean of its divisors is an integer number (9935595519).

Almost surely, 2^19871191037 is an apocalyptic number.

It is an amenable number.

19871191037 is a deficient number, since it is larger than the sum of its proper divisors (1).

19871191037 is an equidigital number, since it uses as much as digits as its factorization.

19871191037 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 95256, while the sum is 47.

The spelling of 19871191037 in words is "nineteen billion, eight hundred seventy-one million, one hundred ninety-one thousand, thirty-seven".