212705280 has 168 divisors, whose sum is σ = 738611172. Its totient is φ = 56623104.

The previous prime is 212705249. The next prime is 212705281. The reversal of 212705280 is 82507212.

It can be written as a sum of positive squares in 2 ways, for example, as 196448256 + 16257024 = 14016^2 + 4032^2 .

It is a super-2 number, since 2×212705280² = 90487072279756800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (212705281) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 368352 + ... + 368928.

Almost surely, 2^212705280 is an apocalyptic number.

212705280 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 212705280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (369305586).

212705280 is an abundant number, since it is smaller than the sum of its proper divisors (525905892).

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

212705280 is an equidigital number, since it uses as much as digits as its factorization.

212705280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 614 (or 587 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 212705280 is about 14584.4190833917. The cubic root of 212705280 is about 596.9336895955.

The spelling of 212705280 in words is "two hundred twelve million, seven hundred five thousand, two hundred eighty".