216776772 has 18 divisors (see below), whose sum is σ = 547963598. Its totient is φ = 72258912.

The previous prime is 216776759. The next prime is 216776779. The reversal of 216776772 is 277677612.

It can be written as a sum of positive squares in only one way, i.e., 193098816 + 23677956 = 13896^2 + 4866^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is not an unprimeable number, because it can be changed into a prime (216776779) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3010753 + ... + 3010824.

Almost surely, 2^216776772 is an apocalyptic number.

It is an amenable number.

216776772 is an abundant number, since it is smaller than the sum of its proper divisors (331186826).

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

216776772 is a wasteful number, since it uses less digits than its factorization.

216776772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6021587 (or 6021582 counting only the distinct ones).

The product of its digits is 345744, while the sum is 45.

The square root of 216776772 is about 14723.3410610500. The cubic root of 216776772 is about 600.7183728907.

The spelling of 216776772 in words is "two hundred sixteen million, seven hundred seventy-six thousand, seven hundred seventy-two".