212778 has 12 divisors (see below), whose sum is σ = 461058. Its totient is φ = 70920.

The previous prime is 212777. The next prime is 212791. The reversal of 212778 is 877212.

212778 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 205209 + 7569 = 453^2 + 87^2 .

It is not an unprimeable number, because it can be changed into a prime (212777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5893 + ... + 5928.

2²¹²⁷⁷⁸ is an apocalyptic number.

212778 is an abundant number, since it is smaller than the sum of its proper divisors (248280).

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

212778 is a wasteful number, since it uses less digits than its factorization.

212778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11829 (or 11826 counting only the distinct ones).

The product of its digits is 1568, while the sum is 27.

The square root of 212778 is about 461.2786576463. The cubic root of 212778 is about 59.7001708706.

It can be divided in two parts, 212 and 778, that added together give a triangular number (990 = T₄₄).

The spelling of 212778 in words is "two hundred twelve thousand, seven hundred seventy-eight".