25919815481 has 4 divisors (see below), whose sum is σ = 29622646272. Its totient is φ = 22216984692.

The previous prime is 25919815417. The next prime is 25919815487. The reversal of 25919815481 is 18451891952.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 25919815481 - 2⁶ = 25919815417 is a prime.

It is a super-2 number, since 2×25919815481² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25919815487) 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, 1851415385 + ... + 1851415398.

It is an arithmetic number, because the mean of its divisors is an integer number (7405661568).

Almost surely, 2^25919815481 is an apocalyptic number.

It is an amenable number.

25919815481 is a deficient number, since it is larger than the sum of its proper divisors (3702830791).

25919815481 is an equidigital number, since it uses as much as digits as its factorization.

25919815481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3702830790.

The product of its digits is 1036800, while the sum is 53.

The spelling of 25919815481 in words is "twenty-five billion, nine hundred nineteen million, eight hundred fifteen thousand, four hundred eighty-one".