216511047 has 24 divisors (see below), whose sum is σ = 317211648. Its totient is φ = 142290000.

The previous prime is 216511039. The next prime is 216511069. The reversal of 216511047 is 740115612.

It is a happy number.

216511047 is a `hidden beast` number, since 2 + 1 + 651 + 1 + 0 + 4 + 7 = 666.

It is not a de Polignac number, because 216511047 - 2³ = 216511039 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 216511047.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216511147) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 287922 + ... + 288672.

It is an arithmetic number, because the mean of its divisors is an integer number (13217152).

Almost surely, 2^216511047 is an apocalyptic number.

216511047 is a deficient number, since it is larger than the sum of its proper divisors (100700601).

216511047 is a wasteful number, since it uses less digits than its factorization.

216511047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1171 (or 1168 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 27.

The square root of 216511047 is about 14714.3143571150. The cubic root of 216511047 is about 600.4728189725.

Adding to 216511047 its reverse (740115612), we get a palindrome (956626659).

The spelling of 216511047 in words is "two hundred sixteen million, five hundred eleven thousand, forty-seven".