216557322009 has 16 divisors (see below), whose sum is σ = 331556060160. Its totient is φ = 123160559760.

The previous prime is 216557321957. The next prime is 216557322061. The reversal of 216557322009 is 900223755612.

It is an interprime number because it is at equal distance from previous prime (216557321957) and next prime (216557322061).

It is not a de Polignac number, because 216557322009 - 2⁸ = 216557321753 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (216557322209) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24432189 + ... + 24441050.

It is an arithmetic number, because the mean of its divisors is an integer number (20722253760).

Almost surely, 2^216557322009 is an apocalyptic number.

It is an amenable number.

216557322009 is a deficient number, since it is larger than the sum of its proper divisors (114998738151).

216557322009 is a wasteful number, since it uses less digits than its factorization.

216557322009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48873460.

The product of its (nonzero) digits is 226800, while the sum is 42.

The spelling of 216557322009 in words is "two hundred sixteen billion, five hundred fifty-seven million, three hundred twenty-two thousand, nine".