20875745 has 32 divisors (see below), whose sum is σ = 29393280. Its totient is φ = 14064640.

The previous prime is 20875721. The next prime is 20875747. The reversal of 20875745 is 54757802.

It is not a de Polignac number, because 20875745 - 2⁶ = 20875681 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20875699 and 20875708.

It is not an unprimeable number, because it can be changed into a prime (20875747) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 77471 + ... + 77739.

It is an arithmetic number, because the mean of its divisors is an integer number (918540).

Almost surely, 2^20875745 is an apocalyptic number.

It is an amenable number.

20875745 is a deficient number, since it is larger than the sum of its proper divisors (8517535).

20875745 is a wasteful number, since it uses less digits than its factorization.

20875745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 385.

The product of its (nonzero) digits is 78400, while the sum is 38.

The square root of 20875745 is about 4568.9982490695. The cubic root of 20875745 is about 275.3471978289.

It can be divided in two parts, 208757 and 45, that added together give a palindrome (208802).

The spelling of 20875745 in words is "twenty million, eight hundred seventy-five thousand, seven hundred forty-five".