216680989 has 8 divisors (see below), whose sum is σ = 252689600. Its totient is φ = 185726268.

The previous prime is 216680987. The next prime is 216681019. The reversal of 216680989 is 989086612.

It is a happy number.

216680989 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 216680989 - 2¹ = 216680987 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216680987) 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, 315519 + ... + 316204.

It is an arithmetic number, because the mean of its divisors is an integer number (31586200).

Almost surely, 2^216680989 is an apocalyptic number.

It is an amenable number.

216680989 is a deficient number, since it is larger than the sum of its proper divisors (36008611).

216680989 is an frugal number, since it uses more digits than its factorization.

216680989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 631744 (or 631730 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 49.

The square root of 216680989 is about 14720.0879413134. The cubic root of 216680989 is about 600.6298838828.

The spelling of 216680989 in words is "two hundred sixteen million, six hundred eighty thousand, nine hundred eighty-nine".