212945 has 4 divisors (see below), whose sum is σ = 255540. Its totient is φ = 170352.

The previous prime is 212923. The next prime is 212969. The reversal of 212945 is 549212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 49729 + 163216 = 223^2 + 404^2 .

It is a cyclic number.

It is not a de Polignac number, because 212945 - 2⁶ = 212881 is a prime.

It is an Ulam number.

It is an alternating number because its digits alternate between even and odd.

It is a self number, because there is not a number n which added to its sum of digits gives 212945.

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, 21290 + ... + 21299.

It is an arithmetic number, because the mean of its divisors is an integer number (63885).

2²¹²⁹⁴⁵ is an apocalyptic number.

It is an amenable number.

212945 is a deficient number, since it is larger than the sum of its proper divisors (42595).

212945 is an equidigital number, since it uses as much as digits as its factorization.

212945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42594.

The product of its digits is 720, while the sum is 23.

The square root of 212945 is about 461.4596407054. The cubic root of 212945 is about 59.7157854570.

The spelling of 212945 in words is "two hundred twelve thousand, nine hundred forty-five".