20310390 has 24 divisors (see below), whose sum is σ = 52807248. Its totient is φ = 5416080.

The previous prime is 20310383. The next prime is 20310391. The reversal of 20310390 is 9301302.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20310391) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 112746 + ... + 112925.

It is an arithmetic number, because the mean of its divisors is an integer number (2200302).

Almost surely, 2^20310390 is an apocalyptic number.

20310390 is an abundant number, since it is smaller than the sum of its proper divisors (32496858).

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

20310390 is a wasteful number, since it uses less digits than its factorization.

20310390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225684 (or 225681 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 18.

The square root of 20310390 is about 4506.7050047679. The cubic root of 20310390 is about 272.8387728936.

Adding to 20310390 its reverse (9301302), we get a palindrome (29611692).

The spelling of 20310390 in words is "twenty million, three hundred ten thousand, three hundred ninety".