2644540243 has 4 divisors (see below), whose sum is σ = 2667943368. Its totient is φ = 2621137120.

The previous prime is 2644540231. The next prime is 2644540277. The reversal of 2644540243 is 3420454462.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3420454462 = 2 ⋅1710227231.

It is a cyclic number.

It is not a de Polignac number, because 2644540243 - 2⁹ = 2644539731 is a prime.

It is a super-3 number, since 3×2644540243³ (a number of 29 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2644540199 and 2644540208.

It is not an unprimeable number, because it can be changed into a prime (2644540643) 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, 11701393 + ... + 11701618.

It is an arithmetic number, because the mean of its divisors is an integer number (666985842).

Almost surely, 2^2644540243 is an apocalyptic number.

2644540243 is a deficient number, since it is larger than the sum of its proper divisors (23403125).

2644540243 is a wasteful number, since it uses less digits than its factorization.

2644540243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23403124.

The product of its (nonzero) digits is 92160, while the sum is 34.

The square root of 2644540243 is about 51425.0935147424. The cubic root of 2644540243 is about 1382.8764902380.

The spelling of 2644540243 in words is "two billion, six hundred forty-four million, five hundred forty thousand, two hundred forty-three".