1001001691 has 2 divisors, whose sum is σ = 1001001692. Its totient is φ = 1001001690.

The previous prime is 1001001647. The next prime is 1001001707. The reversal of 1001001691 is 1961001001.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1001001691 - 2¹⁵ = 1000968923 is a prime.

It is not a weakly prime, because it can be changed into another prime (1001004691) 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, 500500845 + 500500846.

It is an arithmetic number, because the mean of its divisors is an integer number (500500846).

Almost surely, 2^1001001691 is an apocalyptic number.

1001001691 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001001691 is an equidigital number, since it uses as much as digits as its factorization.

1001001691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54, while the sum is 19.

The square root of 1001001691 is about 31638.6107628006. The cubic root of 1001001691 is about 1000.3337855748. Note that the first 3 decimals are identical.

Adding to 1001001691 its reverse (1961001001), we get a palindrome (2962002692).

The spelling of 1001001691 in words is "one billion, one million, one thousand, six hundred ninety-one".