216656031 has 24 divisors (see below), whose sum is σ = 308254720. Its totient is φ = 134973216.

The previous prime is 216656017. The next prime is 216656057. The reversal of 216656031 is 130656612.

It is not a de Polignac number, because 216656031 - 2⁹ = 216655519 is a prime.

It is a super-3 number, since 3×216656031³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 216656031.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216656081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1252261 + ... + 1252433.

Almost surely, 2^216656031 is an apocalyptic number.

216656031 is a deficient number, since it is larger than the sum of its proper divisors (91598689).

216656031 is a wasteful number, since it uses less digits than its factorization.

216656031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 495 (or 322 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 216656031 is about 14719.2401638128. The cubic root of 216656031 is about 600.6068221823.

The spelling of 216656031 in words is "two hundred sixteen million, six hundred fifty-six thousand, thirty-one".