216972 has 72 divisors (see below), whose sum is σ = 670320. Its totient is φ = 60480.

The previous prime is 216967. The next prime is 216973. The reversal of 216972 is 279612.

It is a Harshad number since it is a multiple of its sum of digits (27).

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

216972 is a modest number, since divided by 972 gives 216 as remainder.

It is a plaindrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (216973) by changing a digit.

216972 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5272 + ... + 5312.

It is an arithmetic number, because the mean of its divisors is an integer number (9310).

2²¹⁶⁹⁷² 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 216972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (335160).

216972 is an abundant number, since it is smaller than the sum of its proper divisors (453348).

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

216972 is a wasteful number, since it uses less digits than its factorization.

216972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68 (or 53 counting only the distinct ones).

The product of its digits is 1512, while the sum is 27.

The square root of 216972 is about 465.8025332692. The cubic root of 216972 is about 60.0898653365.

The spelling of 216972 in words is "two hundred sixteen thousand, nine hundred seventy-two".