20775040 has 128 divisors (see below), whose sum is σ = 58605120. Its totient is φ = 6942720.

The previous prime is 20775031. The next prime is 20775043. The reversal of 20775040 is 4057702.

It is a tau number, because it is divible by the number of its divisors (128).

It is a junction number, because it is equal to n+sod(n) for n = 20774996 and 20775014.

It is not an unprimeable number, because it can be changed into a prime (20775043) 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 15 ways as a sum of consecutive naturals, for example, 91407 + ... + 91633.

Almost surely, 2^20775040 is an apocalyptic number.

20775040 is a gapful number since it is divisible by the number (20) 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 20775040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29302560).

20775040 is an abundant number, since it is smaller than the sum of its proper divisors (37830080).

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

20775040 is a wasteful number, since it uses less digits than its factorization.

20775040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270 (or 258 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 25.

The square root of 20775040 is about 4557.9644579571. The cubic root of 20775040 is about 274.9037238739.

It can be divided in two parts, 2077 and 5040, that added together give a palindrome (7117).

The spelling of 20775040 in words is "twenty million, seven hundred seventy-five thousand, forty".