20289408 has 32 divisors (see below), whose sum is σ = 53894760. Its totient is φ = 6763008.

The previous prime is 20289403. The next prime is 20289439. The reversal of 20289408 is 80498202.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20289403) 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 3 ways as a sum of consecutive naturals, for example, 26035 + ... + 26802.

Almost surely, 2^20289408 is an apocalyptic number.

It is an amenable number.

20289408 is an abundant number, since it is smaller than the sum of its proper divisors (33605352).

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

20289408 is an equidigital number, since it uses as much as digits as its factorization.

20289408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52854 (or 52842 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 20289408 is about 4504.3765384346. The cubic root of 20289408 is about 272.7447869156.

It can be divided in two parts, 2028 and 9408, that multiplied together give a square (19079424 = 4368²).

The spelling of 20289408 in words is "twenty million, two hundred eighty-nine thousand, four hundred eight".