2123452665 has 20 divisors (see below), whose sum is σ = 3806486244. Its totient is φ = 1132507872.

The previous prime is 2123452637. The next prime is 2123452693. The reversal of 2123452665 is 5662543212.

2123452665 is a `hidden beast` number, since 2 + 123 + 4 + 526 + 6 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (2123452637) and next prime (2123452693).

It can be written as a sum of positive squares in 2 ways, for example, as 1226330361 + 897122304 = 35019^2 + 29952^2 .

It is not a de Polignac number, because 2123452665 - 2⁷ = 2123452537 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2621142 + ... + 2621951.

Almost surely, 2^2123452665 is an apocalyptic number.

It is an amenable number.

2123452665 is a deficient number, since it is larger than the sum of its proper divisors (1683033579).

2123452665 is an equidigital number, since it uses as much as digits as its factorization.

2123452665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5243110 (or 5243101 counting only the distinct ones).

The product of its digits is 86400, while the sum is 36.

The square root of 2123452665 is about 46080.9360256495. The cubic root of 2123452665 is about 1285.3286698325.

Adding to 2123452665 its reverse (5662543212), we get a palindrome (7785995877).

The spelling of 2123452665 in words is "two billion, one hundred twenty-three million, four hundred fifty-two thousand, six hundred sixty-five".