2640391402678 has 32 divisors (see below), whose sum is σ = 4446034185600. Its totient is φ = 1168671763584.

The previous prime is 2640391402673. The next prime is 2640391402699. The reversal of 2640391402678 is 8762041930462.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2640391402673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14612700 + ... + 14792287.

It is an arithmetic number, because the mean of its divisors is an integer number (138938568300).

Almost surely, 2^{2640391402678} is an apocalyptic number.

2640391402678 is a deficient number, since it is larger than the sum of its proper divisors (1805642782922).

2640391402678 is a wasteful number, since it uses less digits than its factorization.

2640391402678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29405164.

The product of its (nonzero) digits is 3483648, while the sum is 52.

The spelling of 2640391402678 in words is "two trillion, six hundred forty billion, three hundred ninety-one million, four hundred two thousand, six hundred seventy-eight".