216420556 has 12 divisors (see below), whose sum is σ = 413166600. Its totient is φ = 98372960.

The previous prime is 216420521. The next prime is 216420559. The reversal of 216420556 is 655024612.

It is not an unprimeable number, because it can be changed into a prime (216420559) 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 3 ways as a sum of consecutive naturals, for example, 2459281 + ... + 2459368.

It is an arithmetic number, because the mean of its divisors is an integer number (34430550).

Almost surely, 2^216420556 is an apocalyptic number.

It is an amenable number.

216420556 is a deficient number, since it is larger than the sum of its proper divisors (196746044).

216420556 is a wasteful number, since it uses less digits than its factorization.

216420556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4918664 (or 4918662 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 216420556 is about 14711.2391048477. The cubic root of 216420556 is about 600.3891512513.

The spelling of 216420556 in words is "two hundred sixteen million, four hundred twenty thousand, five hundred fifty-six".