216424644 has 12 divisors (see below), whose sum is σ = 504990864. Its totient is φ = 72141544.

The previous prime is 216424643. The next prime is 216424667. The reversal of 216424644 is 446424612.

It is a tau number, because it is divible by the number of its divisors (12).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (216424643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9017682 + ... + 9017705.

It is an arithmetic number, because the mean of its divisors is an integer number (42082572).

Almost surely, 2^216424644 is an apocalyptic number.

It is an amenable number.

216424644 is an abundant number, since it is smaller than the sum of its proper divisors (288566220).

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

216424644 is a wasteful number, since it uses less digits than its factorization.

216424644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18035394 (or 18035392 counting only the distinct ones).

The product of its digits is 36864, while the sum is 33.

The square root of 216424644 is about 14711.3780455809. The cubic root of 216424644 is about 600.3929315074.

The spelling of 216424644 in words is "two hundred sixteen million, four hundred twenty-four thousand, six hundred forty-four".