212206645 has 16 divisors (see below), whose sum is σ = 297220608. Its totient is φ = 142416000.

The previous prime is 212206639. The next prime is 212206667. The reversal of 212206645 is 546602212.

It is not a de Polignac number, because 212206645 - 2⁵ = 212206613 is a prime.

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 (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62856 + ... + 66145.

It is an arithmetic number, because the mean of its divisors is an integer number (18576288).

Almost surely, 2^212206645 is an apocalyptic number.

It is an amenable number.

212206645 is a deficient number, since it is larger than the sum of its proper divisors (85013963).

212206645 is a wasteful number, since it uses less digits than its factorization.

212206645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129060.

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 212206645 is about 14567.3142685946. The cubic root of 212206645 is about 596.4668700847.

Adding to 212206645 its reverse (546602212), we get a palindrome (758808857).

The spelling of 212206645 in words is "two hundred twelve million, two hundred six thousand, six hundred forty-five".