855852565129 has 9 divisors (see below), whose sum is σ = 909174968167. Its totient is φ = 805493494624.

The previous prime is 855852565097. The next prime is 855852565147. The reversal of 855852565129 is 921565258558.

It is a happy number.

The square root of 855852565129 is 925123.

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., 666321201225 + 189531363904 = 816285^2 + 435352^2 .

It is not a de Polignac number, because 855852565129 - 2⁵ = 855852565097 is a prime.

It is a super-2 number, since 2×855852565129² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (855852565199) 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 8 ways as a sum of consecutive naturals, for example, 15699882 + ... + 15754300.

Almost surely, 2^855852565129 is an apocalyptic number.

855852565129 is the 925123-rd square number.

855852565129 is the 462562-nd centered octagonal number.

It is an amenable number.

855852565129 is a deficient number, since it is larger than the sum of its proper divisors (53322403038).

855852565129 is an frugal number, since it uses more digits than its factorization.

855852565129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108872 (or 54436 counting only the distinct ones).

The product of its digits is 43200000, while the sum is 61.

The spelling of 855852565129 in words is "eight hundred fifty-five billion, eight hundred fifty-two million, five hundred sixty-five thousand, one hundred twenty-nine".