211242139 has 8 divisors (see below), whose sum is σ = 217745168. Its totient is φ = 204780960.

The previous prime is 211242137. The next prime is 211242173. The reversal of 211242139 is 931242112.

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 211242139 - 2¹ = 211242137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (211242131) 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, 57 + ... + 20554.

It is an arithmetic number, because the mean of its divisors is an integer number (27218146).

Almost surely, 2^211242139 is an apocalyptic number.

211242139 is a deficient number, since it is larger than the sum of its proper divisors (6503029).

211242139 is a wasteful number, since it uses less digits than its factorization.

211242139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20925.

The product of its digits is 864, while the sum is 25.

The square root of 211242139 is about 14534.1714246117. The cubic root of 211242139 is about 595.5618250990.

The spelling of 211242139 in words is "two hundred eleven million, two hundred forty-two thousand, one hundred thirty-nine".