212566640 has 160 divisors (see below), whose sum is σ = 615335616. Its totient is φ = 67092480.

The previous prime is 212566609. The next prime is 212566649. The reversal of 212566640 is 46665212.

It is a junction number, because it is equal to n+sod(n) for n = 212566597 and 212566606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212566649) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 193934 + ... + 195026.

Almost surely, 2^212566640 is an apocalyptic number.

212566640 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 212566640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (307667808).

212566640 is an abundant number, since it is smaller than the sum of its proper divisors (402768976).

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

212566640 is a wasteful number, since it uses less digits than its factorization.

212566640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1147 (or 1141 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 32.

The square root of 212566640 is about 14579.6652910826. The cubic root of 212566640 is about 596.8039688322.

It can be divided in two parts, 2125 and 66640, that multiplied together give a square (141610000 = 11900²).

The spelling of 212566640 in words is "two hundred twelve million, five hundred sixty-six thousand, six hundred forty".