20776728 has 128 divisors (see below), whose sum is σ = 65433600. Its totient is φ = 5360256.

The previous prime is 20776711. The next prime is 20776739. The reversal of 20776728 is 82767702.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 73275 + ... + 73557.

It is an arithmetic number, because the mean of its divisors is an integer number (511200).

Almost surely, 2^20776728 is an apocalyptic number.

20776728 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20776728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32716800).

20776728 is an abundant number, since it is smaller than the sum of its proper divisors (44656872).

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

20776728 is a wasteful number, since it uses less digits than its factorization.

20776728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341 (or 337 counting only the distinct ones).

The product of its (nonzero) digits is 65856, while the sum is 39.

The square root of 20776728 is about 4558.1496245736. The cubic root of 20776728 is about 274.9111691049.

The spelling of 20776728 in words is "twenty million, seven hundred seventy-six thousand, seven hundred twenty-eight".