1691923693 has 2 divisors, whose sum is σ = 1691923694. Its totient is φ = 1691923692.

The previous prime is 1691923663. The next prime is 1691923703. The reversal of 1691923693 is 3963291961.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1691923689 + 4 = 41133^2 + 2^2 .

It is a cyclic number.

It is not a de Polignac number, because 1691923693 - 2²⁹ = 1155052781 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1691923603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 845961846 + 845961847.

It is an arithmetic number, because the mean of its divisors is an integer number (845961847).

Almost surely, 2^1691923693 is an apocalyptic number.

It is an amenable number.

1691923693 is a deficient number, since it is larger than the sum of its proper divisors (1).

1691923693 is an equidigital number, since it uses as much as digits as its factorization.

1691923693 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 472392, while the sum is 49.

The square root of 1691923693 is about 41133.0000486228. Note that the first 4 decimals coincide. The cubic root of 1691923693 is about 1191.5902034583.

The spelling of 1691923693 in words is "one billion, six hundred ninety-one million, nine hundred twenty-three thousand, six hundred ninety-three".