2091691688 has 32 divisors (see below), whose sum is σ = 3968870400. Its totient is φ = 1033380288.

The previous prime is 2091691687. The next prime is 2091691709. The reversal of 2091691688 is 8861961902.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (2091691687) 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 in 7 ways as a sum of consecutive naturals, for example, 330845 + ... + 337107.

It is an arithmetic number, because the mean of its divisors is an integer number (124027200).

Almost surely, 2^2091691688 is an apocalyptic number.

It is an amenable number.

2091691688 is a deficient number, since it is larger than the sum of its proper divisors (1877178712).

2091691688 is a wasteful number, since it uses less digits than its factorization.

2091691688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6761 (or 6757 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 50.

The square root of 2091691688 is about 45735.0159943123. The cubic root of 2091691688 is about 1278.8881311372. Note that the first 3 decimals are identical.

The spelling of 2091691688 in words is "two billion, ninety-one million, six hundred ninety-one thousand, six hundred eighty-eight".