20305206 has 24 divisors (see below), whose sum is σ = 44108064. Its totient is φ = 6750960.

The previous prime is 20305199. The next prime is 20305211. The reversal of 20305206 is 60250302.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7075 + ... + 9521.

It is an arithmetic number, because the mean of its divisors is an integer number (1837836).

Almost surely, 2^20305206 is an apocalyptic number.

20305206 is an abundant number, since it is smaller than the sum of its proper divisors (23802858).

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

20305206 is a wasteful number, since it uses less digits than its factorization.

20305206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2916 (or 2913 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 20305206 is about 4506.1298250272. The cubic root of 20305206 is about 272.8155579028.

Adding to 20305206 its reverse (60250302), we get a palindrome (80555508).

The spelling of 20305206 in words is "twenty million, three hundred five thousand, two hundred six".