216363638 has 4 divisors (see below), whose sum is σ = 324545460. Its totient is φ = 108181818.

The previous prime is 216363629. The next prime is 216363643. The reversal of 216363638 is 836363612.

It is a semiprime because it is the product of two primes.

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54090908 + ... + 54090911.

It is an arithmetic number, because the mean of its divisors is an integer number (81136365).

Almost surely, 2^216363638 is an apocalyptic number.

216363638 is a deficient number, since it is larger than the sum of its proper divisors (108181822).

216363638 is a wasteful number, since it uses less digits than its factorization.

216363638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108181821.

The product of its digits is 93312, while the sum is 38.

The square root of 216363638 is about 14709.3044703004. The cubic root of 216363638 is about 600.3365130815.

The spelling of 216363638 in words is "two hundred sixteen million, three hundred sixty-three thousand, six hundred thirty-eight".