25721506161023 has 2 divisors, whose sum is σ = 25721506161024. Its totient is φ = 25721506161022.

The previous prime is 25721506161007. The next prime is 25721506161049. The reversal of 25721506161023 is 32016160512752.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25721506161023 - 2⁴ = 25721506161007 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25721506161523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12860753080511 + 12860753080512.

It is an arithmetic number, because the mean of its divisors is an integer number (12860753080512).

Almost surely, 2^{25721506161023} is an apocalyptic number.

25721506161023 is a deficient number, since it is larger than the sum of its proper divisors (1).

25721506161023 is an equidigital number, since it uses as much as digits as its factorization.

25721506161023 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 151200, while the sum is 41.

Adding to 25721506161023 its reverse (32016160512752), we get a palindrome (57737666673775).

The spelling of 25721506161023 in words is "twenty-five trillion, seven hundred twenty-one billion, five hundred six million, one hundred sixty-one thousand, twenty-three".