212721404 has 24 divisors (see below), whose sum is σ = 430832640. Its totient is φ = 90011376.

The previous prime is 212721371. The next prime is 212721419. The reversal of 212721404 is 404127212.

It is a self number, because there is not a number n which added to its sum of digits gives 212721404.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45872 + ... + 50295.

It is an arithmetic number, because the mean of its divisors is an integer number (17951360).

Almost surely, 2^212721404 is an apocalyptic number.

It is an amenable number.

212721404 is an abundant number, since it is smaller than the sum of its proper divisors (218111236).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

212721404 is a wasteful number, since it uses less digits than its factorization.

212721404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96257 (or 96255 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 23.

The square root of 212721404 is about 14584.9718546180. The cubic root of 212721404 is about 596.9487726181.

Adding to 212721404 its reverse (404127212), we get a palindrome (616848616).

The spelling of 212721404 in words is "two hundred twelve million, seven hundred twenty-one thousand, four hundred four".