216039440 has 20 divisors (see below), whose sum is σ = 502291884. Its totient is φ = 86415744.

The previous prime is 216039433. The next prime is 216039449. The reversal of 216039440 is 44930612.

It can be written as a sum of positive squares in 2 ways, for example, as 52301824 + 163737616 = 7232^2 + 12796^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (216039449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1350167 + ... + 1350326.

Almost surely, 2^216039440 is an apocalyptic number.

216039440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216039440 is an abundant number, since it is smaller than the sum of its proper divisors (286252444).

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

216039440 is a wasteful number, since it uses less digits than its factorization.

216039440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2700506 (or 2700500 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 216039440 is about 14698.2801715031. The cubic root of 216039440 is about 600.0365162961.

The spelling of 216039440 in words is "two hundred sixteen million, thirty-nine thousand, four hundred forty".