211688638 has 16 divisors (see below), whose sum is σ = 364723200. Its totient is φ = 90266616.

The previous prime is 211688549. The next prime is 211688647. The reversal of 211688638 is 836886112.

It is a junction number, because it is equal to n+sod(n) for n = 211688594 and 211688603.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35206 + ... + 40777.

It is an arithmetic number, because the mean of its divisors is an integer number (22795200).

Almost surely, 2^211688638 is an apocalyptic number.

211688638 is a deficient number, since it is larger than the sum of its proper divisors (153034562).

211688638 is a wasteful number, since it uses less digits than its factorization.

211688638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76191.

The product of its digits is 110592, while the sum is 43.

The square root of 211688638 is about 14549.5236348136. The cubic root of 211688638 is about 595.9811395170.

The spelling of 211688638 in words is "two hundred eleven million, six hundred eighty-eight thousand, six hundred thirty-eight".