216497 has 4 divisors (see below), whose sum is σ = 218100. Its totient is φ = 214896.

The previous prime is 216493. The next prime is 216509. The reversal of 216497 is 794612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 128881 + 87616 = 359^2 + 296^2 .

It is a cyclic number.

It is not a de Polignac number, because 216497 - 2² = 216493 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 216497.

It is not an unprimeable number, because it can be changed into a prime (216493) 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, 578 + ... + 875.

It is an arithmetic number, because the mean of its divisors is an integer number (54525).

2²¹⁶⁴⁹⁷ is an apocalyptic number.

It is an amenable number.

216497 is a deficient number, since it is larger than the sum of its proper divisors (1603).

216497 is a wasteful number, since it uses less digits than its factorization.

216497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1602.

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

The square root of 216497 is about 465.2923811970. The cubic root of 216497 is about 60.0459832685.

The spelling of 216497 in words is "two hundred sixteen thousand, four hundred ninety-seven".