2091779491 has 2 divisors, whose sum is σ = 2091779492. Its totient is φ = 2091779490.

The previous prime is 2091779477. The next prime is 2091779507. The reversal of 2091779491 is 1949771902.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2091779491 is a prime.

It is not a weakly prime, because it can be changed into another prime (2091779401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1045889745 + 1045889746.

It is an arithmetic number, because the mean of its divisors is an integer number (1045889746).

Almost surely, 2^2091779491 is an apocalyptic number.

2091779491 is a deficient number, since it is larger than the sum of its proper divisors (1).

2091779491 is an equidigital number, since it uses as much as digits as its factorization.

2091779491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 285768, while the sum is 49.

The square root of 2091779491 is about 45735.9758942564. The cubic root of 2091779491 is about 1278.9060255276.

The spelling of 2091779491 in words is "two billion, ninety-one million, seven hundred seventy-nine thousand, four hundred ninety-one".