2541666639 has 4 divisors (see below), whose sum is σ = 3388888856. Its totient is φ = 1694444424.

The previous prime is 2541666529. The next prime is 2541666643. The reversal of 2541666639 is 9366661452.

It is a happy number.

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

It is not a de Polignac number, because 2541666639 - 2²³ = 2533278031 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2541666739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 423611104 + ... + 423611109.

It is an arithmetic number, because the mean of its divisors is an integer number (847222214).

Almost surely, 2^2541666639 is an apocalyptic number.

2541666639 is a deficient number, since it is larger than the sum of its proper divisors (847222217).

2541666639 is an equidigital number, since it uses as much as digits as its factorization.

2541666639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 847222216.

The product of its digits is 1399680, while the sum is 48.

The square root of 2541666639 is about 50414.9445997910. The cubic root of 2541666639 is about 1364.7073467250.

The spelling of 2541666639 in words is "two billion, five hundred forty-one million, six hundred sixty-six thousand, six hundred thirty-nine".