20617056 has 72 divisors (see below), whose sum is σ = 62093304. Its totient is φ = 6466560.

The previous prime is 20617049. The next prime is 20617127. The reversal of 20617056 is 65071602.

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2791 + ... + 7001.

It is an arithmetic number, because the mean of its divisors is an integer number (862407).

Almost surely, 2^20617056 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 20617056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31046652).

20617056 is an abundant number, since it is smaller than the sum of its proper divisors (41476248).

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

20617056 is a wasteful number, since it uses less digits than its factorization.

20617056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4244 (or 4233 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 20617056 is about 4540.6008412984. The cubic root of 20617056 is about 274.2051139663.

Adding to 20617056 its reverse (65071602), we get a palindrome (85688658).

The spelling of 20617056 in words is "twenty million, six hundred seventeen thousand, fifty-six".