215158705857 has 12 divisors (see below), whose sum is σ = 311583735060. Its totient is φ = 143070396768.

The previous prime is 215158705841. The next prime is 215158705891. The reversal of 215158705857 is 758507851512.

215158705857 is a `hidden beast` number, since 2 + 1 + 5 + 1 + 58 + 7 + 0 + 585 + 7 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 131501242161 + 83657463696 = 362631^2 + 289236^2 .

It is not a de Polignac number, because 215158705857 - 2⁴ = 215158705841 is a prime.

It is a super-2 number, since 2×215158705857² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (215158705057) 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 11 ways as a sum of consecutive naturals, for example, 30724678 + ... + 30731679.

It is an arithmetic number, because the mean of its divisors is an integer number (25965311255).

Almost surely, 2^215158705857 is an apocalyptic number.

It is an amenable number.

215158705857 is a deficient number, since it is larger than the sum of its proper divisors (96425029203).

215158705857 is a wasteful number, since it uses less digits than its factorization.

215158705857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61456752 (or 61456749 counting only the distinct ones).

The product of its (nonzero) digits is 3920000, while the sum is 54.

The spelling of 215158705857 in words is "two hundred fifteen billion, one hundred fifty-eight million, seven hundred five thousand, eight hundred fifty-seven".