20571408 has 240 divisors, whose sum is σ = 72037056. Its totient is φ = 5598720.

The previous prime is 20571403. The next prime is 20571409. The reversal of 20571408 is 80417502.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (20571401) 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 47 ways as a sum of consecutive naturals, for example, 555966 + ... + 556002.

Almost surely, 2^20571408 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20571408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36018528).

20571408 is an abundant number, since it is smaller than the sum of its proper divisors (51465648).

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

20571408 is a wasteful number, since it uses less digits than its factorization.

20571408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84 (or 66 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 20571408 is about 4535.5714083233. The cubic root of 20571408 is about 274.0025929035.

The spelling of 20571408 in words is "twenty million, five hundred seventy-one thousand, four hundred eight".