211245138 has 64 divisors (see below), whose sum is σ = 510209280. Its totient is φ = 64399104.

The previous prime is 211245113. The next prime is 211245143. The reversal of 211245138 is 831542112.

211245138 is a `hidden beast` number, since 21 + 124 + 513 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 77995 + ... + 80657.

It is an arithmetic number, because the mean of its divisors is an integer number (7972020).

Almost surely, 2^211245138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 211245138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (255104640).

211245138 is an abundant number, since it is smaller than the sum of its proper divisors (298964142).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

211245138 is a wasteful number, since it uses less digits than its factorization.

211245138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2800 (or 2794 counting only the distinct ones).

The product of its digits is 1920, while the sum is 27.

The square root of 211245138 is about 14534.2745949015. The cubic root of 211245138 is about 595.5646434783.

It can be divided in two parts, 21124 and 5138, that added together give a palindrome (26262).

The spelling of 211245138 in words is "two hundred eleven million, two hundred forty-five thousand, one hundred thirty-eight".