212817 has 8 divisors (see below), whose sum is σ = 309600. Its totient is φ = 128960.

The previous prime is 212801. The next prime is 212827. The reversal of 212817 is 718212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 212817 - 2⁴ = 212801 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 212793 and 212802.

It is not an unprimeable number, because it can be changed into a prime (212827) 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 7 ways as a sum of consecutive naturals, for example, 3192 + ... + 3257.

It is an arithmetic number, because the mean of its divisors is an integer number (38700).

2²¹²⁸¹⁷ is an apocalyptic number.

It is an amenable number.

212817 is a deficient number, since it is larger than the sum of its proper divisors (96783).

212817 is a wasteful number, since it uses less digits than its factorization.

212817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6463.

The product of its digits is 224, while the sum is 21.

The square root of 212817 is about 461.3209295057. The cubic root of 212817 is about 59.7038181218.

It can be divided in two parts, 2128 and 17, that added together give a triangular number (2145 = T₆₅).

The spelling of 212817 in words is "two hundred twelve thousand, eight hundred seventeen".