25991220449 has 32 divisors (see below), whose sum is σ = 29576275200. Its totient is φ = 22707336960.

The previous prime is 25991220427. The next prime is 25991220469. The reversal of 25991220449 is 94402219952.

It is a happy number.

It is not a de Polignac number, because 25991220449 - 2¹² = 25991216353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25991220419) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13445087 + ... + 13447019.

It is an arithmetic number, because the mean of its divisors is an integer number (924258600).

Almost surely, 2^25991220449 is an apocalyptic number.

25991220449 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

25991220449 is a deficient number, since it is larger than the sum of its proper divisors (3585054751).

25991220449 is a wasteful number, since it uses less digits than its factorization.

25991220449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3065.

The product of its (nonzero) digits is 466560, while the sum is 47.

The spelling of 25991220449 in words is "twenty-five billion, nine hundred ninety-one million, two hundred twenty thousand, four hundred forty-nine".