216500531 has 4 divisors (see below), whose sum is σ = 233154432. Its totient is φ = 199846632.

The previous prime is 216500521. The next prime is 216500549. The reversal of 216500531 is 135005612.

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

It is a cyclic number.

It is not a de Polignac number, because 216500531 - 2⁶ = 216500467 is a prime.

It is a super-2 number, since 2×216500531² = 93744959846563922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 216500497 and 216500506.

It is not an unprimeable number, because it can be changed into a prime (216500521) 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, 8326931 + ... + 8326956.

It is an arithmetic number, because the mean of its divisors is an integer number (58288608).

Almost surely, 2^216500531 is an apocalyptic number.

216500531 is a deficient number, since it is larger than the sum of its proper divisors (16653901).

216500531 is a wasteful number, since it uses less digits than its factorization.

216500531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16653900.

The product of its (nonzero) digits is 900, while the sum is 23.

The square root of 216500531 is about 14713.9570136656. The cubic root of 216500531 is about 600.4630971061.

The spelling of 216500531 in words is "two hundred sixteen million, five hundred thousand, five hundred thirty-one".