211975638840 has 384 divisors, whose sum is σ = 809699829120. Its totient is φ = 47079014400.

The previous prime is 211975638821. The next prime is 211975638851. The reversal of 211975638840 is 48836579112.

211975638840 is a `hidden beast` number, since 21 + 19 + 7 + 563 + 8 + 8 + 40 = 666.

211975638840 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×211975638840² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 123169180 + ... + 123170900.

It is an arithmetic number, because the mean of its divisors is an integer number (2108593305).

It is a 2-persistent number, because it is pandigital, and so is 2⋅211975638840 = 423951277680, but 3⋅211975638840 = 635926916520 is not.

Almost surely, 2^211975638840 is an apocalyptic number.

211975638840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 211975638840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (404849914560).

211975638840 is an abundant number, since it is smaller than the sum of its proper divisors (597724190280).

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

211975638840 is a wasteful number, since it uses less digits than its factorization.

211975638840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3103 (or 3096 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The spelling of 211975638840 in words is "two hundred eleven billion, nine hundred seventy-five million, six hundred thirty-eight thousand, eight hundred forty".