212645780 has 12 divisors (see below), whose sum is σ = 446556180. Its totient is φ = 85058304.

The previous prime is 212645779. The next prime is 212645863. The reversal of 212645780 is 87546212.

It can be written as a sum of positive squares in 2 ways, for example, as 149475076 + 63170704 = 12226^2 + 7948^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 212645780.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5316125 + ... + 5316164.

It is an arithmetic number, because the mean of its divisors is an integer number (37213015).

Almost surely, 2^212645780 is an apocalyptic number.

212645780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212645780 is an abundant number, since it is smaller than the sum of its proper divisors (233910400).

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

212645780 is a wasteful number, since it uses less digits than its factorization.

212645780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10632298 (or 10632296 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 35.

The square root of 212645780 is about 14582.3790925898. The cubic root of 212645780 is about 596.8780243627.

The spelling of 212645780 in words is "two hundred twelve million, six hundred forty-five thousand, seven hundred eighty".