216763921 has 8 divisors (see below), whose sum is σ = 236815488. Its totient is φ = 196770000.

The previous prime is 216763919. The next prime is 216763931. The reversal of 216763921 is 129367612.

216763921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 216763921 - 2¹ = 216763919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216763931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6345 + ... + 21766.

It is an arithmetic number, because the mean of its divisors is an integer number (29601936).

Almost surely, 2^216763921 is an apocalyptic number.

It is an amenable number.

216763921 is a deficient number, since it is larger than the sum of its proper divisors (20051567).

216763921 is a wasteful number, since it uses less digits than its factorization.

216763921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28823.

The product of its digits is 27216, while the sum is 37.

The square root of 216763921 is about 14722.9046386914. The cubic root of 216763921 is about 600.7065020242.

The spelling of 216763921 in words is "two hundred sixteen million, seven hundred sixty-three thousand, nine hundred twenty-one".