2578126643 has 4 divisors (see below), whose sum is σ = 2579904888. Its totient is φ = 2576348400.

The previous prime is 2578126637. The next prime is 2578126697. The reversal of 2578126643 is 3466218752.

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

It is a cyclic number.

It is not a de Polignac number, because 2578126643 - 2⁴ = 2578126627 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2578126594 and 2578126603.

It is not an unprimeable number, because it can be changed into a prime (2578125643) 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, 886946 + ... + 889847.

It is an arithmetic number, because the mean of its divisors is an integer number (644976222).

Almost surely, 2^2578126643 is an apocalyptic number.

2578126643 is a deficient number, since it is larger than the sum of its proper divisors (1778245).

2578126643 is a wasteful number, since it uses less digits than its factorization.

2578126643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1778244.

The product of its digits is 483840, while the sum is 44.

The square root of 2578126643 is about 50775.2562081177. The cubic root of 2578126643 is about 1371.2019293901.

The spelling of 2578126643 in words is "two billion, five hundred seventy-eight million, one hundred twenty-six thousand, six hundred forty-three".