25043236643 has 4 divisors (see below), whose sum is σ = 25453781568. Its totient is φ = 24632691720.

The previous prime is 25043236637. The next prime is 25043236657. The reversal of 25043236643 is 34663234052.

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 25043236643 - 2³⁰ = 23969494819 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25043236597 and 25043236606.

It is not an unprimeable number, because it can be changed into a prime (27043236643) 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, 205272371 + ... + 205272492.

It is an arithmetic number, because the mean of its divisors is an integer number (6363445392).

Almost surely, 2^25043236643 is an apocalyptic number.

25043236643 is a deficient number, since it is larger than the sum of its proper divisors (410544925).

25043236643 is an equidigital number, since it uses as much as digits as its factorization.

25043236643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410544924.

The product of its (nonzero) digits is 311040, while the sum is 38.

The spelling of 25043236643 in words is "twenty-five billion, forty-three million, two hundred thirty-six thousand, six hundred forty-three".