216536621 has 8 divisors (see below), whose sum is σ = 253506624. Its totient is φ = 181075680.

The previous prime is 216536611. The next prime is 216536623. The reversal of 216536621 is 126635612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 216536621 - 2⁶ = 216536557 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216536623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 376955 + ... + 377528.

It is an arithmetic number, because the mean of its divisors is an integer number (31688328).

Almost surely, 2^216536621 is an apocalyptic number.

It is an amenable number.

216536621 is a deficient number, since it is larger than the sum of its proper divisors (36970003).

216536621 is an equidigital number, since it uses as much as digits as its factorization.

216536621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 754531.

The product of its digits is 12960, while the sum is 32.

The square root of 216536621 is about 14715.1833491805. The cubic root of 216536621 is about 600.4964603948.

The spelling of 216536621 in words is "two hundred sixteen million, five hundred thirty-six thousand, six hundred twenty-one".