1991936719 has 2 divisors, whose sum is σ = 1991936720. Its totient is φ = 1991936718.

The previous prime is 1991936711. The next prime is 1991936729. The reversal of 1991936719 is 9176391991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1991936719 - 2³ = 1991936711 is a prime.

It is a super-2 number, since 2×1991936719² = 7935623785000969922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1991936719.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1991936711) 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, 995968359 + 995968360.

It is an arithmetic number, because the mean of its divisors is an integer number (995968360).

Almost surely, 2^1991936719 is an apocalyptic number.

1991936719 is a deficient number, since it is larger than the sum of its proper divisors (1).

1991936719 is an equidigital number, since it uses as much as digits as its factorization.

1991936719 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 826686, while the sum is 55.

The square root of 1991936719 is about 44631.1182808587. The cubic root of 1991936719 is about 1258.2255864392.

The spelling of 1991936719 in words is "one billion, nine hundred ninety-one million, nine hundred thirty-six thousand, seven hundred nineteen".