211994663 has 4 divisors (see below), whose sum is σ = 212043720. Its totient is φ = 211945608.

The previous prime is 211994659. The next prime is 211994681. The reversal of 211994663 is 366499112.

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

It is a cyclic number.

It is not a de Polignac number, because 211994663 - 2² = 211994659 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 211994663.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211994603) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17345 + ... + 26922.

It is an arithmetic number, because the mean of its divisors is an integer number (53010930).

Almost surely, 2^211994663 is an apocalyptic number.

211994663 is a deficient number, since it is larger than the sum of its proper divisors (49057).

211994663 is an equidigital number, since it uses as much as digits as its factorization.

211994663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49056.

The product of its digits is 69984, while the sum is 41.

The square root of 211994663 is about 14560.0365040751. The cubic root of 211994663 is about 596.2681921002.

The spelling of 211994663 in words is "two hundred eleven million, nine hundred ninety-four thousand, six hundred sixty-three".