8661391519 has 4 divisors (see below), whose sum is σ = 9448790760. Its totient is φ = 7873992280.

The previous prime is 8661391511. The next prime is 8661391631. The reversal of 8661391519 is 9151931668.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 8661391519 - 2³ = 8661391511 is a prime.

It is a super-2 number, since 2×8661391519² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8661391511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 393699604 + ... + 393699625.

It is an arithmetic number, because the mean of its divisors is an integer number (2362197690).

Almost surely, 2^8661391519 is an apocalyptic number.

8661391519 is a deficient number, since it is larger than the sum of its proper divisors (787399241).

8661391519 is a wasteful number, since it uses less digits than its factorization.

8661391519 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 787399240.

The product of its digits is 349920, while the sum is 49.

The square root of 8661391519 is about 93066.5972247831. The cubic root of 8661391519 is about 2053.6632117591.

The spelling of 8661391519 in words is "eight billion, six hundred sixty-one million, three hundred ninety-one thousand, five hundred nineteen".