8166521259 has 72 divisors (see below), whose sum is σ = 13086707712. Its totient is φ = 4903778880.

The previous prime is 8166521161. The next prime is 8166521269. The reversal of 8166521259 is 9521256618.

It is not a de Polignac number, because 8166521259 - 2¹⁶ = 8166455723 is a prime.

It is not an unprimeable number, because it can be changed into a prime (8166521269) 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 71 ways as a sum of consecutive naturals, for example, 12941874 + ... + 12942504.

Almost surely, 2^8166521259 is an apocalyptic number.

8166521259 is a deficient number, since it is larger than the sum of its proper divisors (4920186453).

8166521259 is a wasteful number, since it uses less digits than its factorization.

8166521259 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 857 (or 841 counting only the distinct ones).

The product of its digits is 259200, while the sum is 45.

The square root of 8166521259 is about 90368.8068915375. The cubic root of 8166521259 is about 2013.7815873775.

The spelling of 8166521259 in words is "eight billion, one hundred sixty-six million, five hundred twenty-one thousand, two hundred fifty-nine".