2645288381 has 4 divisors (see below), whose sum is σ = 2646424572. Its totient is φ = 2644152192.

The previous prime is 2645288339. The next prime is 2645288411. The reversal of 2645288381 is 1838825462.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1586827225 + 1058461156 = 39835^2 + 32534^2 .

It is a cyclic number.

It is not a de Polignac number, because 2645288381 - 2¹⁰ = 2645287357 is a prime.

It is a super-2 number, since 2×2645288381² = 13995101237307202322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2645288081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 564596 + ... + 569261.

It is an arithmetic number, because the mean of its divisors is an integer number (661606143).

Almost surely, 2^2645288381 is an apocalyptic number.

It is an amenable number.

2645288381 is a deficient number, since it is larger than the sum of its proper divisors (1136191).

2645288381 is a wasteful number, since it uses less digits than its factorization.

2645288381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1136190.

The product of its digits is 737280, while the sum is 47.

The square root of 2645288381 is about 51432.3670561642. The cubic root of 2645288381 is about 1383.0068827714.

The spelling of 2645288381 in words is "two billion, six hundred forty-five million, two hundred eighty-eight thousand, three hundred eighty-one".