20305508 has 6 divisors (see below), whose sum is σ = 35534646. Its totient is φ = 10152752.

The previous prime is 20305507. The next prime is 20305513. The reversal of 20305508 is 80550302.

It can be written as a sum of positive squares in only one way, i.e., 16176484 + 4129024 = 4022^2 + 2032^2 .

It is not an unprimeable number, because it can be changed into a prime (20305507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2538185 + ... + 2538192.

It is an arithmetic number, because the mean of its divisors is an integer number (5922441).

Almost surely, 2^20305508 is an apocalyptic number.

It is an amenable number.

20305508 is a deficient number, since it is larger than the sum of its proper divisors (15229138).

20305508 is a wasteful number, since it uses less digits than its factorization.

20305508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5076381 (or 5076379 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 20305508 is about 4506.1633348116. The cubic root of 20305508 is about 272.8169104277.

The spelling of 20305508 in words is "twenty million, three hundred five thousand, five hundred eight".