866158272 has 140 divisors (see below), whose sum is σ = 2934482320. Its totient is φ = 247463424.

The previous prime is 866158247. The next prime is 866158273. The reversal of 866158272 is 272851668.

866158272 is a `hidden beast` number, since 8 + 6 + 61 + 582 + 7 + 2 = 666.

It is not an unprimeable number, because it can be changed into a prime (866158273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 24354 + ... + 48222.

It is an arithmetic number, because the mean of its divisors is an integer number (20960588).

Almost surely, 2^866158272 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 866158272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1467241160).

866158272 is an abundant number, since it is smaller than the sum of its proper divisors (2068324048).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

866158272 is a wasteful number, since it uses less digits than its factorization.

866158272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23900 (or 23881 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The square root of 866158272 is about 29430.5669670158. The cubic root of 866158272 is about 953.2330373021.

The spelling of 866158272 in words is "eight hundred sixty-six million, one hundred fifty-eight thousand, two hundred seventy-two".