20581064 has 16 divisors (see below), whose sum is σ = 44102400. Its totient is φ = 8820432.

The previous prime is 20581051. The next prime is 20581069. The reversal of 20581064 is 46018502.

It is a super-3 number, since 3×20581064³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (20581069) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 183704 + ... + 183815.

It is an arithmetic number, because the mean of its divisors is an integer number (2756400).

Almost surely, 2^20581064 is an apocalyptic number.

It is an amenable number.

20581064 is an abundant number, since it is smaller than the sum of its proper divisors (23521336).

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

20581064 is a wasteful number, since it uses less digits than its factorization.

20581064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 367532 (or 367528 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 20581064 is about 4536.6357579158. The cubic root of 20581064 is about 274.0454574979.

Adding to 20581064 its reverse (46018502), we get a palindrome (66599566).

The spelling of 20581064 in words is "twenty million, five hundred eighty-one thousand, sixty-four".