20887135 has 16 divisors (see below), whose sum is σ = 26920512. Its totient is φ = 15500800.

The previous prime is 20887133. The next prime is 20887147. The reversal of 20887135 is 53178802.

It is not a de Polignac number, because 20887135 - 2¹ = 20887133 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20887135.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20887133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4305 + ... + 7765.

It is an arithmetic number, because the mean of its divisors is an integer number (1682532).

Almost surely, 2^20887135 is an apocalyptic number.

20887135 is a deficient number, since it is larger than the sum of its proper divisors (6033377).

20887135 is a wasteful number, since it uses less digits than its factorization.

20887135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3554.

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 20887135 is about 4570.2445229987. The cubic root of 20887135 is about 275.3972660520.

The spelling of 20887135 in words is "twenty million, eight hundred eighty-seven thousand, one hundred thirty-five".