1491116161 has 2 divisors, whose sum is σ = 1491116162. Its totient is φ = 1491116160.

The previous prime is 1491116153. The next prime is 1491116173. The reversal of 1491116161 is 1616111941.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 872847936 + 618268225 = 29544^2 + 24865^2 .

It is a cyclic number.

It is not a de Polignac number, because 1491116161 - 2³ = 1491116153 is a prime.

It is not a weakly prime, because it can be changed into another prime (1491116131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 745558080 + 745558081.

It is an arithmetic number, because the mean of its divisors is an integer number (745558081).

Almost surely, 2^1491116161 is an apocalyptic number.

It is an amenable number.

1491116161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1491116161 is an equidigital number, since it uses as much as digits as its factorization.

1491116161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 31.

The square root of 1491116161 is about 38614.9732746250. The cubic root of 1491116161 is about 1142.4498870521.

The spelling of 1491116161 in words is "one billion, four hundred ninety-one million, one hundred sixteen thousand, one hundred sixty-one".