25821253391 has 2 divisors, whose sum is σ = 25821253392. Its totient is φ = 25821253390.

The previous prime is 25821253379. The next prime is 25821253487. The reversal of 25821253391 is 19335212852.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25821253391 - 2¹⁰ = 25821252367 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25821253331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12910626695 + 12910626696.

It is an arithmetic number, because the mean of its divisors is an integer number (12910626696).

Almost surely, 2^25821253391 is an apocalyptic number.

25821253391 is a deficient number, since it is larger than the sum of its proper divisors (1).

25821253391 is an equidigital number, since it uses as much as digits as its factorization.

25821253391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129600, while the sum is 41.

The spelling of 25821253391 in words is "twenty-five billion, eight hundred twenty-one million, two hundred fifty-three thousand, three hundred ninety-one".