20887560 has 96 divisors (see below), whose sum is σ = 71898840. Its totient is φ = 5240832.

The previous prime is 20887549. The next prime is 20887567. The reversal of 20887560 is 6578802.

It can be written as a sum of positive squares in 4 ways, for example, as 20848356 + 39204 = 4566^2 + 198^2 .

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (20887567) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 4414 + ... + 7826.

Almost surely, 2^20887560 is an apocalyptic number.

20887560 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 20887560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35949420).

20887560 is an abundant number, since it is smaller than the sum of its proper divisors (51011280).

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

20887560 is a wasteful number, since it uses less digits than its factorization.

20887560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3447 (or 3440 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 20887560 is about 4570.2910191803. The cubic root of 20887560 is about 275.3991339170.

The spelling of 20887560 in words is "twenty million, eight hundred eighty-seven thousand, five hundred sixty".