217964 has 12 divisors (see below), whose sum is σ = 394800. Its totient is φ = 105168.

The previous prime is 217937. The next prime is 217969. The reversal of 217964 is 469712.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a plaindrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (217969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 824 + ... + 1055.

It is an arithmetic number, because the mean of its divisors is an integer number (32900).

2²¹⁷⁹⁶⁴ is an apocalyptic number.

It is an amenable number.

217964 is a deficient number, since it is larger than the sum of its proper divisors (176836).

217964 is a wasteful number, since it uses less digits than its factorization.

217964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1912 (or 1910 counting only the distinct ones).

The product of its digits is 3024, while the sum is 29.

The square root of 217964 is about 466.8661478411. The cubic root of 217964 is about 60.1813034510.

The spelling of 217964 in words is "two hundred seventeen thousand, nine hundred sixty-four".