216562456081 has 16 divisors (see below), whose sum is σ = 221873983056. Its totient is φ = 211299618816.

The previous prime is 216562456069. The next prime is 216562456091. The reversal of 216562456081 is 180654265612.

It can be written as a sum of positive squares in 8 ways, for example, as 6651870481 + 209910585600 = 81559^2 + 458160^2 .

It is a cyclic number.

It is not a de Polignac number, because 216562456081 - 2²⁹ = 216025585169 is a prime.

It is a super-2 number, since 2×216562456081² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216562456031) 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, 6962941 + ... + 6993973.

It is an arithmetic number, because the mean of its divisors is an integer number (13867123941).

Almost surely, 2^216562456081 is an apocalyptic number.

It is an amenable number.

216562456081 is a deficient number, since it is larger than the sum of its proper divisors (5311526975).

216562456081 is a wasteful number, since it uses less digits than its factorization.

216562456081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31812.

The product of its (nonzero) digits is 691200, while the sum is 46.

The spelling of 216562456081 in words is "two hundred sixteen billion, five hundred sixty-two million, four hundred fifty-six thousand, eighty-one".