216428656 has 40 divisors (see below), whose sum is σ = 426031760. Its totient is φ = 106500096.

The previous prime is 216428623. The next prime is 216428657. The reversal of 216428656 is 656824612.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216428657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 336271 + ... + 336913.

It is an arithmetic number, because the mean of its divisors is an integer number (10650794).

Almost surely, 2^216428656 is an apocalyptic number.

It is an amenable number.

216428656 is a deficient number, since it is larger than the sum of its proper divisors (209603104).

216428656 is a wasteful number, since it uses less digits than its factorization.

216428656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 953 (or 947 counting only the distinct ones).

The product of its digits is 138240, while the sum is 40.

The square root of 216428656 is about 14711.5144019914. The cubic root of 216428656 is about 600.3966414385.

The spelling of 216428656 in words is "two hundred sixteen million, four hundred twenty-eight thousand, six hundred fifty-six".