13640637447 has 6 divisors (see below), whose sum is σ = 19703142992. Its totient is φ = 9093758292.

The previous prime is 13640637443. The next prime is 13640637457. The reversal of 13640637447 is 74473604631.

13640637447 is a `hidden beast` number, since 1 + 3 + 6 + 4 + 0 + 637 + 4 + 4 + 7 = 666.

It is not a de Polignac number, because 13640637447 - 2² = 13640637443 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13640637443) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 757813183 + ... + 757813200.

Almost surely, 2^13640637447 is an apocalyptic number.

13640637447 is a deficient number, since it is larger than the sum of its proper divisors (6062505545).

13640637447 is a wasteful number, since it uses less digits than its factorization.

13640637447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1515626389 (or 1515626386 counting only the distinct ones).

The product of its (nonzero) digits is 1016064, while the sum is 45.

The spelling of 13640637447 in words is "thirteen billion, six hundred forty million, six hundred thirty-seven thousand, four hundred forty-seven".