25501556243 has 2 divisors, whose sum is σ = 25501556244. Its totient is φ = 25501556242.

The previous prime is 25501556237. The next prime is 25501556263. The reversal of 25501556243 is 34265510552.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25501556243 - 2²⁰ = 25500507667 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 25501556197 and 25501556206.

It is not a weakly prime, because it can be changed into another prime (25501556263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12750778121 + 12750778122.

It is an arithmetic number, because the mean of its divisors is an integer number (12750778122).

Almost surely, 2^25501556243 is an apocalyptic number.

25501556243 is a deficient number, since it is larger than the sum of its proper divisors (1).

25501556243 is an equidigital number, since it uses as much as digits as its factorization.

25501556243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 180000, while the sum is 38.

The spelling of 25501556243 in words is "twenty-five billion, five hundred one million, five hundred fifty-six thousand, two hundred forty-three".