2691428009 has 4 divisors (see below), whose sum is σ = 2692229316. Its totient is φ = 2690626704.

The previous prime is 2691427873. The next prime is 2691428023. The reversal of 2691428009 is 9008241962.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2675785984 + 15642025 = 51728^2 + 3955^2 .

It is a cyclic number.

It is not a de Polignac number, because 2691428009 - 2²⁸ = 2422992553 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2691428059) 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 3 ways as a sum of consecutive naturals, for example, 395594 + ... + 402339.

It is an arithmetic number, because the mean of its divisors is an integer number (673057329).

Almost surely, 2^2691428009 is an apocalyptic number.

It is an amenable number.

2691428009 is a deficient number, since it is larger than the sum of its proper divisors (801307).

2691428009 is an equidigital number, since it uses as much as digits as its factorization.

2691428009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 801306.

The product of its (nonzero) digits is 62208, while the sum is 41.

The square root of 2691428009 is about 51878.9746332751. The cubic root of 2691428009 is about 1391.0014708899.

The spelling of 2691428009 in words is "two billion, six hundred ninety-one million, four hundred twenty-eight thousand, nine".