20305090 has 32 divisors (see below), whose sum is σ = 41078016. Its totient is φ = 7170240.

The previous prime is 20305079. The next prime is 20305097. The reversal of 20305090 is 9050302.

It is not an unprimeable number, because it can be changed into a prime (20305097) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 406 + ... + 6385.

It is an arithmetic number, because the mean of its divisors is an integer number (1283688).

Almost surely, 2^20305090 is an apocalyptic number.

20305090 is an abundant number, since it is smaller than the sum of its proper divisors (20772926).

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

20305090 is a wasteful number, since it uses less digits than its factorization.

20305090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6834.

The product of its (nonzero) digits is 270, while the sum is 19.

The square root of 20305090 is about 4506.1169536531. The cubic root of 20305090 is about 272.8150383863.

Adding to 20305090 its reverse (9050302), we get a palindrome (29355392).

The spelling of 20305090 in words is "twenty million, three hundred five thousand, ninety".