217542 has 16 divisors (see below), whose sum is σ = 468720. Its totient is φ = 66912.

The previous prime is 217519. The next prime is 217559. The reversal of 217542 is 245712.

217542 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a plaindrome in base 15.

It is a congruent number.

It is an unprimeable number.

217542 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 7 ways as a sum of consecutive naturals, for example, 1317 + ... + 1472.

It is an arithmetic number, because the mean of its divisors is an integer number (29295).

2²¹⁷⁵⁴² is an apocalyptic number.

217542 is an abundant number, since it is smaller than the sum of its proper divisors (251178).

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

217542 is a wasteful number, since it uses less digits than its factorization.

217542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2807.

The product of its digits is 560, while the sum is 21.

The square root of 217542 is about 466.4139792073. The cubic root of 217542 is about 60.1424393607.

The spelling of 217542 in words is "two hundred seventeen thousand, five hundred forty-two".