2781387 has 48 divisors (see below), whose sum is σ = 5054400. Its totient is φ = 1467648.

The previous prime is 2781379. The next prime is 2781397. The reversal of 2781387 is 7831872.

2781387 is a `hidden beast` number, since 278 + 1 + 387 = 666.

2781387 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2781387 - 2³ = 2781379 is a prime.

It is a super-2 number, since 2×2781387² = 15472227287538, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2781307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 52453 + ... + 52505.

It is an arithmetic number, because the mean of its divisors is an integer number (105300).

2^2781387 is an apocalyptic number.

2781387 is a deficient number, since it is larger than the sum of its proper divisors (2273013).

2781387 is a wasteful number, since it uses less digits than its factorization.

2781387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97 (or 80 counting only the distinct ones).

The product of its digits is 18816, while the sum is 36.

The square root of 2781387 is about 1667.7490818465. The cubic root of 2781387 is about 140.6329672523.

The spelling of 2781387 in words is "two million, seven hundred eighty-one thousand, three hundred eighty-seven".