26440005663 has 20 divisors (see below), whose sum is σ = 39846341568. Its totient is φ = 17470676160.

The previous prime is 26440005637. The next prime is 26440005671. The reversal of 26440005663 is 36650004462.

26440005663 is a `hidden beast` number, since 2 + 644 + 0 + 0 + 0 + 5 + 6 + 6 + 3 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-26440005663 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26440005863) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1435183 + ... + 1453488.

Almost surely, 2^26440005663 is an apocalyptic number.

26440005663 is a deficient number, since it is larger than the sum of its proper divisors (13406335905).

26440005663 is a wasteful number, since it uses less digits than its factorization.

26440005663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2888796 (or 2888787 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 36.

The spelling of 26440005663 in words is "twenty-six billion, four hundred forty million, five thousand, six hundred sixty-three".