861216 has 24 divisors (see below), whose sum is σ = 2260944. Its totient is φ = 287040.

The previous prime is 861199. The next prime is 861221. The reversal of 861216 is 612168.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4390 + ... + 4581.

It is an arithmetic number, because the mean of its divisors is an integer number (94206).

2⁸⁶¹²¹⁶ is an apocalyptic number.

It is an amenable number.

861216 is an abundant number, since it is smaller than the sum of its proper divisors (1399728).

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

861216 is a wasteful number, since it uses less digits than its factorization.

861216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8984 (or 8976 counting only the distinct ones).

The product of its digits is 576, while the sum is 24.

The square root of 861216 is about 928.0172412191. The cubic root of 861216 is about 95.1416538652.

The spelling of 861216 in words is "eight hundred sixty-one thousand, two hundred sixteen".