216021366 has 24 divisors (see below), whose sum is σ = 510596424. Its totient is φ = 65460960.

The previous prime is 216021349. The next prime is 216021367. The reversal of 216021366 is 663120612.

216021366 is a `hidden beast` number, since 21 + 602 + 1 + 36 + 6 = 666.

216021366 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216021367) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 545311 + ... + 545706.

It is an arithmetic number, because the mean of its divisors is an integer number (21274851).

Almost surely, 2^216021366 is an apocalyptic number.

216021366 is an abundant number, since it is smaller than the sum of its proper divisors (294575058).

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

216021366 is a wasteful number, since it uses less digits than its factorization.

216021366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1091036 (or 1091033 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 216021366 is about 14697.6653248058. The cubic root of 216021366 is about 600.0197826811.

Adding to 216021366 its reverse (663120612), we get a palindrome (879141978).

The spelling of 216021366 in words is "two hundred sixteen million, twenty-one thousand, three hundred sixty-six".