20609816 has 8 divisors (see below), whose sum is σ = 38643420. Its totient is φ = 10304904.

The previous prime is 20609801. The next prime is 20609843. The reversal of 20609816 is 61890602.

It is a tau number, because it is divible by the number of its divisors (8).

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, 1288106 + ... + 1288121.

Almost surely, 2^20609816 is an apocalyptic number.

It is an amenable number.

20609816 is a deficient number, since it is larger than the sum of its proper divisors (18033604).

20609816 is a wasteful number, since it uses less digits than its factorization.

20609816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2576233 (or 2576229 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 20609816 is about 4539.8035199775. The cubic root of 20609816 is about 274.1730130777.

The spelling of 20609816 in words is "twenty million, six hundred nine thousand, eight hundred sixteen".