2781642385 has 4 divisors (see below), whose sum is σ = 3337970868. Its totient is φ = 2225313904.

The previous prime is 2781642371. The next prime is 2781642397. The reversal of 2781642385 is 5832461872.

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 1607689216 + 1173953169 = 40096^2 + 34263^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2781642385 is a prime.

It is a Duffinian 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 3 ways as a sum of consecutive naturals, for example, 278164234 + ... + 278164243.

It is an arithmetic number, because the mean of its divisors is an integer number (834492717).

Almost surely, 2^2781642385 is an apocalyptic number.

It is an amenable number.

2781642385 is a deficient number, since it is larger than the sum of its proper divisors (556328483).

2781642385 is an equidigital number, since it uses as much as digits as its factorization.

2781642385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 556328482.

The product of its digits is 645120, while the sum is 46.

The square root of 2781642385 is about 52741.2778097004. The cubic root of 2781642385 is about 1406.3727139398.

The spelling of 2781642385 in words is "two billion, seven hundred eighty-one million, six hundred forty-two thousand, three hundred eighty-five".