20909212 has 6 divisors (see below), whose sum is σ = 36591128. Its totient is φ = 10454604.

The previous prime is 20909209. The next prime is 20909281. The reversal of 20909212 is 21290902.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 2613648 + ... + 2613655.

Almost surely, 2^20909212 is an apocalyptic number.

It is an amenable number.

20909212 is a deficient number, since it is larger than the sum of its proper divisors (15681916).

20909212 is a wasteful number, since it uses less digits than its factorization.

20909212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5227307 (or 5227305 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 20909212 is about 4572.6591825764. The cubic root of 20909212 is about 275.4942604395.

The spelling of 20909212 in words is "twenty million, nine hundred nine thousand, two hundred twelve".