215998 has 4 divisors (see below), whose sum is σ = 324000. Its totient is φ = 107998.

The previous prime is 215983. The next prime is 216023. The reversal of 215998 is 899512.

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

It is a plaindrome in base 16.

It is a congruent number.

It is an unprimeable number.

215998 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 as a sum of consecutive naturals, namely, 53998 + ... + 54001.

It is an arithmetic number, because the mean of its divisors is an integer number (81000).

2²¹⁵⁹⁹⁸ is an apocalyptic number.

215998 is a deficient number, since it is larger than the sum of its proper divisors (108002).

215998 is a wasteful number, since it uses less digits than its factorization.

215998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108001.

The product of its digits is 6480, while the sum is 34.

The square root of 215998 is about 464.7558498825. The cubic root of 215998 is about 59.9998148142. Note that the first 3 decimals are identical.

The spelling of 215998 in words is "two hundred fifteen thousand, nine hundred ninety-eight".