20709536 has 24 divisors (see below), whose sum is σ = 43171380. Its totient is φ = 9745408.

The previous prime is 20709523. The next prime is 20709539. The reversal of 20709536 is 63590702.

It can be written as a sum of positive squares in 2 ways, for example, as 19749136 + 960400 = 4444^2 + 980^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is not an unprimeable number, because it can be changed into a prime (20709539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18491 + ... + 19578.

Almost surely, 2^20709536 is an apocalyptic number.

It is an amenable number.

20709536 is an abundant number, since it is smaller than the sum of its proper divisors (22461844).

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

20709536 is a wasteful number, since it uses less digits than its factorization.

20709536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38096 (or 38088 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 32.

The square root of 20709536 is about 4550.7731211301. The cubic root of 20709536 is about 274.6144945471.

The spelling of 20709536 in words is "twenty million, seven hundred nine thousand, five hundred thirty-six".