2781138945 has 16 divisors (see below), whose sum is σ = 4792116672. Its totient is φ = 1369176000.

The previous prime is 2781138923. The next prime is 2781138961. The reversal of 2781138945 is 5498311872.

It is not a de Polignac number, because 2781138945 - 2¹² = 2781134849 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2781138894 and 2781138903.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 7130931 + ... + 7131320.

It is an arithmetic number, because the mean of its divisors is an integer number (299507292).

Almost surely, 2^2781138945 is an apocalyptic number.

It is an amenable number.

2781138945 is a deficient number, since it is larger than the sum of its proper divisors (2010977727).

2781138945 is a wasteful number, since it uses less digits than its factorization.

2781138945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14262272.

The product of its digits is 483840, while the sum is 48.

The square root of 2781138945 is about 52736.5048614335. The cubic root of 2781138945 is about 1406.2878639484.

The spelling of 2781138945 in words is "two billion, seven hundred eighty-one million, one hundred thirty-eight thousand, nine hundred forty-five".