2543691 has 8 divisors (see below), whose sum is σ = 3404944. Its totient is φ = 1689120.

The previous prime is 2543657. The next prime is 2543699. The reversal of 2543691 is 1963452.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2543691 - 2¹⁹ = 2019403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2543699) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 700 + ... + 2361.

It is an arithmetic number, because the mean of its divisors is an integer number (425618).

2^2543691 is an apocalyptic number.

2543691 is a deficient number, since it is larger than the sum of its proper divisors (861253).

2543691 is a wasteful number, since it uses less digits than its factorization.

2543691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3341.

The product of its digits is 6480, while the sum is 30.

The square root of 2543691 is about 1594.8952943689. The cubic root of 2543691 is about 136.5069566689.

The spelling of 2543691 in words is "two million, five hundred forty-three thousand, six hundred ninety-one".