216343640 has 16 divisors (see below), whose sum is σ = 486773280. Its totient is φ = 86537440.

The previous prime is 216343639. The next prime is 216343643. The reversal of 216343640 is 46343612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216343643) 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, 2704256 + ... + 2704335.

It is an arithmetic number, because the mean of its divisors is an integer number (30423330).

Almost surely, 2^216343640 is an apocalyptic number.

216343640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216343640 is an abundant number, since it is smaller than the sum of its proper divisors (270429640).

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

216343640 is a wasteful number, since it uses less digits than its factorization.

216343640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5408602 (or 5408598 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 29.

The square root of 216343640 is about 14708.6246807783. The cubic root of 216343640 is about 600.3180165978.

The spelling of 216343640 in words is "two hundred sixteen million, three hundred forty-three thousand, six hundred forty".