212005105 has 8 divisors (see below), whose sum is σ = 273975912. Its totient is φ = 156557568.

The previous prime is 212005081. The next prime is 212005127. The reversal of 212005105 is 501500212.

212005105 is digitally balanced in base 2, 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 4 ways, for example, as 26718561 + 185286544 = 5169^2 + 13612^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 212005105 - 2¹³ = 211996913 is a prime.

It is a super-2 number, since 2×212005105² = 89892329092122050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1630744 + ... + 1630873.

It is an arithmetic number, because the mean of its divisors is an integer number (34246989).

Almost surely, 2^212005105 is an apocalyptic number.

It is an amenable number.

212005105 is a deficient number, since it is larger than the sum of its proper divisors (61970807).

212005105 is a wasteful number, since it uses less digits than its factorization.

212005105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3261635.

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 212005105 is about 14560.3950839254. The cubic root of 212005105 is about 596.2779818596.

Adding to 212005105 its reverse (501500212), we get a palindrome (713505317).

The spelling of 212005105 in words is "two hundred twelve million, five thousand, one hundred five".