211438109 has 4 divisors (see below), whose sum is σ = 213103104. Its totient is φ = 209773116.

The previous prime is 211438093. The next prime is 211438121. The reversal of 211438109 is 901834112.

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 a cyclic number.

It is not a de Polignac number, because 211438109 - 2⁴ = 211438093 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 (211431109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 832307 + ... + 832560.

It is an arithmetic number, because the mean of its divisors is an integer number (53275776).

Almost surely, 2^211438109 is an apocalyptic number.

It is an amenable number.

211438109 is a deficient number, since it is larger than the sum of its proper divisors (1664995).

211438109 is a wasteful number, since it uses less digits than its factorization.

211438109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1664994.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 211438109 is about 14540.9115601464. The cubic root of 211438109 is about 595.7459363730.

The spelling of 211438109 in words is "two hundred eleven million, four hundred thirty-eight thousand, one hundred nine".