217532139 has 32 divisors (see below), whose sum is σ = 327254784. Its totient is φ = 127370880.

The previous prime is 217532129. The next prime is 217532167. The reversal of 217532139 is 931235712.

It is not a de Polignac number, because 217532139 - 2⁴ = 217532123 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (217532129) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 198477 + ... + 199569.

It is an arithmetic number, because the mean of its divisors is an integer number (10226712).

Almost surely, 2^217532139 is an apocalyptic number.

217532139 is a deficient number, since it is larger than the sum of its proper divisors (109722645).

217532139 is a wasteful number, since it uses less digits than its factorization.

217532139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1307.

The product of its digits is 11340, while the sum is 33.

The square root of 217532139 is about 14748.9707776509. The cubic root of 217532139 is about 601.4153061116.

The spelling of 217532139 in words is "two hundred seventeen million, five hundred thirty-two thousand, one hundred thirty-nine".