212405505 has 16 divisors (see below), whose sum is σ = 365991360. Its totient is φ = 104568768.

The previous prime is 212405449. The next prime is 212405519. The reversal of 212405505 is 505504212.

It is a happy number.

It is not a de Polignac number, because 212405505 - 2¹⁰ = 212404481 is a prime.

It is a nialpdrome in base 11.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 544435 + ... + 544824.

It is an arithmetic number, because the mean of its divisors is an integer number (22874460).

Almost surely, 2^212405505 is an apocalyptic number.

It is an amenable number.

212405505 is a deficient number, since it is larger than the sum of its proper divisors (153585855).

212405505 is a wasteful number, since it uses less digits than its factorization.

212405505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1089280.

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 212405505 is about 14574.1382249518. The cubic root of 212405505 is about 596.6531293635.

Adding to 212405505 its reverse (505504212), we get a palindrome (717909717).

The spelling of 212405505 in words is "two hundred twelve million, four hundred five thousand, five hundred five".