25515553197 has 4 divisors (see below), whose sum is σ = 34020737600. Its totient is φ = 17010368796.

The previous prime is 25515553159. The next prime is 25515553199. The reversal of 25515553197 is 79135551552.

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 25515553197 - 2²³ = 25507164589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25515553199) 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, 4252592197 + ... + 4252592202.

It is an arithmetic number, because the mean of its divisors is an integer number (8505184400).

Almost surely, 2^25515553197 is an apocalyptic number.

It is an amenable number.

25515553197 is a deficient number, since it is larger than the sum of its proper divisors (8505184403).

25515553197 is an equidigital number, since it uses as much as digits as its factorization.

25515553197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8505184402.

The product of its digits is 1181250, while the sum is 48.

The spelling of 25515553197 in words is "twenty-five billion, five hundred fifteen million, five hundred fifty-three thousand, one hundred ninety-seven".