20311305 has 16 divisors (see below), whose sum is σ = 37140864. Its totient is φ = 9285120.

The previous prime is 20311297. The next prime is 20311307. The reversal of 20311305 is 50311302.

It is a happy number.

It is not a de Polignac number, because 20311305 - 2³ = 20311297 is a prime.

It is a super-2 number, since 2×20311305² = 825098221606050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (20311307) 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 15 ways as a sum of consecutive naturals, for example, 96616 + ... + 96825.

It is an arithmetic number, because the mean of its divisors is an integer number (2321304).

Almost surely, 2^20311305 is an apocalyptic number.

It is an amenable number.

20311305 is a deficient number, since it is larger than the sum of its proper divisors (16829559).

20311305 is a wasteful number, since it uses less digits than its factorization.

It is an anagram of its base 11 representation: 20311305 = (10513203)₁₁.

20311305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193456.

The product of its (nonzero) digits is 90, while the sum is 15.

The square root of 20311305 is about 4506.8065190332. The cubic root of 20311305 is about 272.8428700368.

Adding to 20311305 its reverse (50311302), we get a palindrome (70622607).

The spelling of 20311305 in words is "twenty million, three hundred eleven thousand, three hundred five".