1990694567737 has 2 divisors, whose sum is σ = 1990694567738. Its totient is φ = 1990694567736.

The previous prime is 1990694567711. The next prime is 1990694567777. The reversal of 1990694567737 is 7377654960991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1685398536441 + 305296031296 = 1298229^2 + 552536^2 .

It is a cyclic number.

It is not a de Polignac number, because 1990694567737 - 2²³ = 1990686179129 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1990694567737.

It is not a weakly prime, because it can be changed into another prime (1990694567777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 995347283868 + 995347283869.

It is an arithmetic number, because the mean of its divisors is an integer number (995347283869).

Almost surely, 2^{1990694567737} is an apocalyptic number.

It is an amenable number.

1990694567737 is a deficient number, since it is larger than the sum of its proper divisors (1).

1990694567737 is an equidigital number, since it uses as much as digits as its factorization.

1990694567737 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 540101520, while the sum is 73.

The spelling of 1990694567737 in words is "one trillion, nine hundred ninety billion, six hundred ninety-four million, five hundred sixty-seven thousand, seven hundred thirty-seven".