20708736 has 64 divisors (see below), whose sum is σ = 55488000. Its totient is φ = 6842880.

The previous prime is 20708729. The next prime is 20708741. The reversal of 20708736 is 63780702.

It is a tau number, because it is divible by the number of its divisors (64).

It is a junction number, because it is equal to n+sod(n) for n = 20708697 and 20708706.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76281 + ... + 76551.

It is an arithmetic number, because the mean of its divisors is an integer number (867000).

Almost surely, 2^20708736 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20708736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27744000).

20708736 is an abundant number, since it is smaller than the sum of its proper divisors (34779264).

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

20708736 is a wasteful number, since it uses less digits than its factorization.

20708736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 487 (or 475 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 33.

The square root of 20708736 is about 4550.6852231285. The cubic root of 20708736 is about 274.6109584237.

The spelling of 20708736 in words is "twenty million, seven hundred eight thousand, seven hundred thirty-six".