20311265 has 24 divisors (see below), whose sum is σ = 27032040. Its totient is φ = 14650272.

The previous prime is 20311211. The next prime is 20311273. The reversal of 20311265 is 56211302.

It can be written as a sum of positive squares in 4 ways, for example, as 7573504 + 12737761 = 2752^2 + 3569^2 .

It is not a de Polignac number, because 20311265 - 2²⁰ = 19262689 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 472334 + ... + 472376.

It is an arithmetic number, because the mean of its divisors is an integer number (1126335).

Almost surely, 2^20311265 is an apocalyptic number.

It is an amenable number.

20311265 is a deficient number, since it is larger than the sum of its proper divisors (6720775).

20311265 is an frugal number, since it uses more digits than its factorization.

20311265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130 (or 61 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 20311265 is about 4506.8020812989. The cubic root of 20311265 is about 272.8426909293.

Adding to 20311265 its reverse (56211302), we get a palindrome (76522567).

The spelling of 20311265 in words is "twenty million, three hundred eleven thousand, two hundred sixty-five".