211994813 has 4 divisors (see below), whose sum is σ = 212031840. Its totient is φ = 211957788.

The previous prime is 211994807. The next prime is 211994819. The reversal of 211994813 is 318499112.

211994813 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (211994807) and next prime (211994819).

It is a cyclic number.

It is not a de Polignac number, because 211994813 - 2²⁰ = 210946237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211994819) 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, 7895 + ... + 22052.

It is an arithmetic number, because the mean of its divisors is an integer number (53007960).

Almost surely, 2^211994813 is an apocalyptic number.

It is an amenable number.

211994813 is a deficient number, since it is larger than the sum of its proper divisors (37027).

211994813 is an equidigital number, since it uses as much as digits as its factorization.

211994813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37026.

The product of its digits is 15552, while the sum is 38.

The square root of 211994813 is about 14560.0416551602. The cubic root of 211994813 is about 596.2683327330.

The spelling of 211994813 in words is "two hundred eleven million, nine hundred ninety-four thousand, eight hundred thirteen".