20615056 has 80 divisors (see below), whose sum is σ = 51603840. Its totient is φ = 7741440.

The previous prime is 20615053. The next prime is 20615059. The reversal of 20615056 is 65051602.

It is an interprime number because it is at equal distance from previous prime (20615053) and next prime (20615059).

It is a self number, because there is not a number n which added to its sum of digits gives 20615056.

It is not an unprimeable number, because it can be changed into a prime (20615051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35440 + ... + 36016.

It is an arithmetic number, because the mean of its divisors is an integer number (645048).

Almost surely, 2^20615056 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 20615056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25801920).

20615056 is an abundant number, since it is smaller than the sum of its proper divisors (30988784).

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

20615056 is a wasteful number, since it uses less digits than its factorization.

20615056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 632 (or 626 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 20615056 is about 4540.3806007867. The cubic root of 20615056 is about 274.1962470689.

Adding to 20615056 its reverse (65051602), we get a palindrome (85666658).

It can be divided in two parts, 2061 and 5056, that added together give a palindrome (7117).

The spelling of 20615056 in words is "twenty million, six hundred fifteen thousand, fifty-six".