20557089 has 24 divisors (see below), whose sum is σ = 34856640. Its totient is φ = 11428128.

The previous prime is 20557087. The next prime is 20557091. The reversal of 20557089 is 98075502.

20557089 is a `hidden beast` number, since 2 + 0 + 5 + 570 + 89 = 666.

It is an interprime number because it is at equal distance from previous prime (20557087) and next prime (20557091).

It is not a de Polignac number, because 20557089 - 2¹ = 20557087 is a prime.

It is a super-3 number, since 3×20557089³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (20557087) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2079 + ... + 6740.

It is an arithmetic number, because the mean of its divisors is an integer number (1452360).

Almost surely, 2^20557089 is an apocalyptic number.

It is an amenable number.

20557089 is a deficient number, since it is larger than the sum of its proper divisors (14299551).

20557089 is a wasteful number, since it uses less digits than its factorization.

20557089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8869 (or 8866 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 36.

The square root of 20557089 is about 4533.9926113747. The cubic root of 20557089 is about 273.9390037737.

The spelling of 20557089 in words is "twenty million, five hundred fifty-seven thousand, eighty-nine".