216334705581 has 32 divisors (see below), whose sum is σ = 324220665600. Its totient is φ = 142548215040.

The previous prime is 216334705547. The next prime is 216334705583. The reversal of 216334705581 is 185507433612.

It is a happy number.

216334705581 is a `hidden beast` number, since 2 + 1 + 63 + 3 + 4 + 7 + 0 + 5 + 581 = 666.

It is not a de Polignac number, because 216334705581 - 2²⁹ = 215797834669 is a prime.

It is a super-2 number, since 2×216334705581² (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 (216334705583) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6849616 + ... + 6881126.

It is an arithmetic number, because the mean of its divisors is an integer number (10131895800).

Almost surely, 2^216334705581 is an apocalyptic number.

It is an amenable number.

216334705581 is a deficient number, since it is larger than the sum of its proper divisors (107885960019).

216334705581 is a wasteful number, since it uses less digits than its factorization.

216334705581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34466 (or 34460 counting only the distinct ones).

The product of its (nonzero) digits is 604800, while the sum is 45.

The spelling of 216334705581 in words is "two hundred sixteen billion, three hundred thirty-four million, seven hundred five thousand, five hundred eighty-one".