216671433381 has 16 divisors (see below), whose sum is σ = 345686617920. Its totient is φ = 133336266480.

The previous prime is 216671433379. The next prime is 216671433389. The reversal of 216671433381 is 183334176612.

216671433381 is a `hidden beast` number, since 2 + 166 + 71 + 43 + 3 + 381 = 666.

It is not a de Polignac number, because 216671433381 - 2¹ = 216671433379 is a prime.

It is a super-2 number, since 2×216671433381² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216671433389) 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, 308648415 + ... + 308649116.

It is an arithmetic number, because the mean of its divisors is an integer number (21605413620).

Almost surely, 2^216671433381 is an apocalyptic number.

It is an amenable number.

216671433381 is a deficient number, since it is larger than the sum of its proper divisors (129015184539).

216671433381 is a wasteful number, since it uses less digits than its factorization.

216671433381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 617297553 (or 617297547 counting only the distinct ones).

The product of its digits is 435456, while the sum is 45.

The spelling of 216671433381 in words is "two hundred sixteen billion, six hundred seventy-one million, four hundred thirty-three thousand, three hundred eighty-one".