866515851 has 6 divisors (see below), whose sum is σ = 1251634020. Its totient is φ = 577677228.

The previous prime is 866515847. The next prime is 866515873. The reversal of 866515851 is 158515668.

866515851 is a `hidden beast` number, since 8 + 6 + 65 + 1 + 585 + 1 = 666.

It is not a de Polignac number, because 866515851 - 2² = 866515847 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 866515797 and 866515806.

It is not an unprimeable number, because it can be changed into a prime (866515151) 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 5 ways as a sum of consecutive naturals, for example, 48139761 + ... + 48139778.

It is an arithmetic number, because the mean of its divisors is an integer number (208605670).

Almost surely, 2^866515851 is an apocalyptic number.

866515851 is a deficient number, since it is larger than the sum of its proper divisors (385118169).

866515851 is a wasteful number, since it uses less digits than its factorization.

866515851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96279545 (or 96279542 counting only the distinct ones).

The product of its digits is 288000, while the sum is 45.

The square root of 866515851 is about 29436.6412995776. The cubic root of 866515851 is about 953.3641947101.

The spelling of 866515851 in words is "eight hundred sixty-six million, five hundred fifteen thousand, eight hundred fifty-one".