231505065 has 144 divisors (see below), whose sum is σ = 486250128. Its totient is φ = 101376000.

The previous prime is 231505019. The next prime is 231505091. The reversal of 231505065 is 560505132.

231505065 is a `hidden beast` number, since 2 + 3 + 150 + 506 + 5 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 54641664 + 176863401 = 7392^2 + 13299^2 .

It is not a de Polignac number, because 231505065 - 2⁷ = 231504937 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 3795135 + ... + 3795195.

It is an arithmetic number, because the mean of its divisors is an integer number (3376737).

Almost surely, 2^231505065 is an apocalyptic number.

It is an amenable number.

231505065 is an abundant number, since it is smaller than the sum of its proper divisors (254745063).

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

231505065 is a wasteful number, since it uses less digits than its factorization.

231505065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152 (or 138 counting only the distinct ones).

The product of its (nonzero) digits is 4500, while the sum is 27.

The square root of 231505065 is about 15215.2905000200. The cubic root of 231505065 is about 614.0261008473.

The spelling of 231505065 in words is "two hundred thirty-one million, five hundred five thousand, sixty-five".