212566140 has 96 divisors (see below), whose sum is σ = 677517120. Its totient is φ = 55296000.

The previous prime is 212566139. The next prime is 212566141. The reversal of 212566140 is 41665212.

212566140 is a `hidden beast` number, since 21 + 25 + 6 + 614 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (212566139) and next prime (212566141).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212566141) 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 31 ways as a sum of consecutive naturals, for example, 17340 + ... + 26940.

It is an arithmetic number, because the mean of its divisors is an integer number (7057470).

Almost surely, 2^212566140 is an apocalyptic number.

212566140 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 212566140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (338758560).

212566140 is an abundant number, since it is smaller than the sum of its proper divisors (464950980).

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

212566140 is a wasteful number, since it uses less digits than its factorization.

212566140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9660 (or 9652 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 212566140 is about 14579.6481439025. The cubic root of 212566140 is about 596.8035008971.

It can be divided in two parts, 2125 and 66140, that added together give a triangular number (68265 = T₃₆₉).

The spelling of 212566140 in words is "two hundred twelve million, five hundred sixty-six thousand, one hundred forty".