20605636 has 12 divisors (see below), whose sum is σ = 36465660. Its totient is φ = 10186880.

The previous prime is 20605621. The next prime is 20605661. The reversal of 20605636 is 63650602.

It can be written as a sum of positive squares in 2 ways, for example, as 1943236 + 18662400 = 1394^2 + 4320^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28585 + ... + 29296.

It is an arithmetic number, because the mean of its divisors is an integer number (3038805).

Almost surely, 2^20605636 is an apocalyptic number.

It is an amenable number.

20605636 is a deficient number, since it is larger than the sum of its proper divisors (15860024).

20605636 is a wasteful number, since it uses less digits than its factorization.

20605636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57974 (or 57972 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 28.

The square root of 20605636 is about 4539.3431242857. The cubic root of 20605636 is about 274.1544762685.

The spelling of 20605636 in words is "twenty million, six hundred five thousand, six hundred thirty-six".