216117856 has 24 divisors (see below), whose sum is σ = 447877080. Its totient is φ = 102371328.

The previous prime is 216117841. The next prime is 216117857. The reversal of 216117856 is 658711612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216117857) 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, 177121 + ... + 178336.

It is an arithmetic number, because the mean of its divisors is an integer number (18661545).

Almost surely, 2^216117856 is an apocalyptic number.

It is an amenable number.

216117856 is an abundant number, since it is smaller than the sum of its proper divisors (231759224).

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

216117856 is a wasteful number, since it uses less digits than its factorization.

216117856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355486 (or 355478 counting only the distinct ones).

The product of its digits is 20160, while the sum is 37.

The square root of 216117856 is about 14700.9474524603. The cubic root of 216117856 is about 600.1091060845.

The spelling of 216117856 in words is "two hundred sixteen million, one hundred seventeen thousand, eight hundred fifty-six".