8191155025 has 27 divisors (see below), whose sum is σ = 10631351451. Its totient is φ = 6260049840.

The previous prime is 8191155023. The next prime is 8191155059. The reversal of 8191155025 is 5205511918.

The square root of 8191155025 is 90505.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 2948815809 + 5242339216 = 54303^2 + 72404^2 .

It is not a de Polignac number, because 8191155025 - 2¹ = 8191155023 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8191155023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 10407682 + ... + 10408468.

Almost surely, 2^8191155025 is an apocalyptic number.

8191155025 is the 90505-th square number.

8191155025 is the 45253-rd centered octagonal number.

It is an amenable number.

8191155025 is a deficient number, since it is larger than the sum of its proper divisors (2440196426).

8191155025 is an frugal number, since it uses more digits than its factorization.

8191155025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1630 (or 815 counting only the distinct ones).

The product of its (nonzero) digits is 18000, while the sum is 37.

The cubic root of 8191155025 is about 2015.8043674363.

It can be divided in two parts, 8191 and 155025, that added together give a square (163216 = 404²).

The spelling of 8191155025 in words is "eight billion, one hundred ninety-one million, one hundred fifty-five thousand, twenty-five".