1331949691 has 2 divisors, whose sum is σ = 1331949692. Its totient is φ = 1331949690.

The previous prime is 1331949679. The next prime is 1331949713. The reversal of 1331949691 is 1969491331.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1331949691 - 2⁵ = 1331949659 is a prime.

It is not a weakly prime, because it can be changed into another prime (1331949601) 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, 665974845 + 665974846.

It is an arithmetic number, because the mean of its divisors is an integer number (665974846).

Almost surely, 2^1331949691 is an apocalyptic number.

1331949691 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331949691 is an equidigital number, since it uses as much as digits as its factorization.

1331949691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 157464, while the sum is 46.

The square root of 1331949691 is about 36495.8859462269. The cubic root of 1331949691 is about 1100.2615606656.

The spelling of 1331949691 in words is "one billion, three hundred thirty-one million, nine hundred forty-nine thousand, six hundred ninety-one".