212798561 has 4 divisors (see below), whose sum is σ = 216287124. Its totient is φ = 209310000.

The previous prime is 212798527. The next prime is 212798591. The reversal of 212798561 is 165897212.

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 52649536 + 160149025 = 7256^2 + 12655^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212798561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (212798501) by changing a digit.

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, 1744190 + ... + 1744311.

It is an arithmetic number, because the mean of its divisors is an integer number (54071781).

Almost surely, 2^212798561 is an apocalyptic number.

It is an amenable number.

212798561 is a deficient number, since it is larger than the sum of its proper divisors (3488563).

212798561 is an equidigital number, since it uses as much as digits as its factorization.

212798561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3488562.

The product of its digits is 60480, while the sum is 41.

The square root of 212798561 is about 14587.6167004758. The cubic root of 212798561 is about 597.0209377567.

The spelling of 212798561 in words is "two hundred twelve million, seven hundred ninety-eight thousand, five hundred sixty-one".