2640780811 has 4 divisors (see below), whose sum is σ = 2755597392. Its totient is φ = 2525964232.

The previous prime is 2640780773. The next prime is 2640780841. The reversal of 2640780811 is 1180870462.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2640780811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2640780841) by changing a digit.

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, 57408256 + ... + 57408301.

It is an arithmetic number, because the mean of its divisors is an integer number (688899348).

Almost surely, 2^2640780811 is an apocalyptic number.

2640780811 is a deficient number, since it is larger than the sum of its proper divisors (114816581).

2640780811 is a wasteful number, since it uses less digits than its factorization.

2640780811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114816580.

The product of its (nonzero) digits is 21504, while the sum is 37.

The square root of 2640780811 is about 51388.5280096638. The cubic root of 2640780811 is about 1382.2208884924.

The spelling of 2640780811 in words is "two billion, six hundred forty million, seven hundred eighty thousand, eight hundred eleven".