212646643 has 4 divisors (see below), whose sum is σ = 231978168. Its totient is φ = 193315120.

The previous prime is 212646607. The next prime is 212646673. The reversal of 212646643 is 346646212.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212646643 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212646599 and 212646608.

It is not an unprimeable number, because it can be changed into a prime (212646673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9665746 + ... + 9665767.

It is an arithmetic number, because the mean of its divisors is an integer number (57994542).

Almost surely, 2^212646643 is an apocalyptic number.

212646643 is a deficient number, since it is larger than the sum of its proper divisors (19331525).

212646643 is a wasteful number, since it uses less digits than its factorization.

212646643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19331524.

The product of its digits is 41472, while the sum is 34.

The square root of 212646643 is about 14582.4086830674. The cubic root of 212646643 is about 596.8788318166.

The spelling of 212646643 in words is "two hundred twelve million, six hundred forty-six thousand, six hundred forty-three".