212689285 has 4 divisors (see below), whose sum is σ = 255227148. Its totient is φ = 170151424.

The previous prime is 212689247. The next prime is 212689291. The reversal of 212689285 is 582986212.

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 34680321 + 178008964 = 5889^2 + 13342^2 .

It is a cyclic number.

It is not a de Polignac number, because 212689285 - 2²⁵ = 179134853 is a prime.

It is a super-2 number, since 2×212689285² = 90473463907622450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21268924 + ... + 21268933.

It is an arithmetic number, because the mean of its divisors is an integer number (63806787).

Almost surely, 2^212689285 is an apocalyptic number.

It is an amenable number.

212689285 is a deficient number, since it is larger than the sum of its proper divisors (42537863).

212689285 is an equidigital number, since it uses as much as digits as its factorization.

212689285 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42537862.

The product of its digits is 138240, while the sum is 43.

The square root of 212689285 is about 14583.8707139086. The cubic root of 212689285 is about 596.9187264915.

The spelling of 212689285 in words is "two hundred twelve million, six hundred eighty-nine thousand, two hundred eighty-five".