20311330 has 16 divisors (see below), whose sum is σ = 39372984. Its totient is φ = 7499520.

The previous prime is 20311321. The next prime is 20311331. The reversal of 20311330 is 3311302.

It can be written as a sum of positive squares in 4 ways, for example, as 5031049 + 15280281 = 2243^2 + 3909^2 .

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a self number, because there is not a number n which added to its sum of digits gives 20311330.

It is not an unprimeable number, because it can be changed into a prime (20311331) 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 in 7 ways as a sum of consecutive naturals, for example, 77991 + ... + 78250.

Almost surely, 2^20311330 is an apocalyptic number.

20311330 is a deficient number, since it is larger than the sum of its proper divisors (19061654).

20311330 is a wasteful number, since it uses less digits than its factorization.

20311330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156261.

The product of its (nonzero) digits is 54, while the sum is 13.

The square root of 20311330 is about 4506.8092926149. The cubic root of 20311330 is about 272.8429819789.

Adding to 20311330 its reverse (3311302), we get a palindrome (23622632).

The spelling of 20311330 in words is "twenty million, three hundred eleven thousand, three hundred thirty".