2691787649 has 2 divisors, whose sum is σ = 2691787650. Its totient is φ = 2691787648.

The previous prime is 2691787643. The next prime is 2691787669. The reversal of 2691787649 is 9467871962.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1686580624 + 1005207025 = 41068^2 + 31705^2 .

It is a cyclic number.

It is not a de Polignac number, because 2691787649 - 2⁸ = 2691787393 is a prime.

It is not a weakly prime, because it can be changed into another prime (2691787643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1345893824 + 1345893825.

It is an arithmetic number, because the mean of its divisors is an integer number (1345893825).

Almost surely, 2^2691787649 is an apocalyptic number.

It is an amenable number.

2691787649 is a deficient number, since it is larger than the sum of its proper divisors (1).

2691787649 is an equidigital number, since it uses as much as digits as its factorization.

2691787649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9144576, while the sum is 59.

The square root of 2691787649 is about 51882.4406615572. The cubic root of 2691787649 is about 1391.0634252981.

The spelling of 2691787649 in words is "two billion, six hundred ninety-one million, seven hundred eighty-seven thousand, six hundred forty-nine".