13640403641 has 2 divisors, whose sum is σ = 13640403642. Its totient is φ = 13640403640.

The previous prime is 13640403629. The next prime is 13640403661. The reversal of 13640403641 is 14630404631.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8249907241 + 5390496400 = 90829^2 + 73420^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13640403641 is a prime.

It is a super-2 number, since 2×13640403641² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 13640403598 and 13640403607.

It is not a weakly prime, because it can be changed into another prime (13640403661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6820201820 + 6820201821.

It is an arithmetic number, because the mean of its divisors is an integer number (6820201821).

Almost surely, 2^13640403641 is an apocalyptic number.

It is an amenable number.

13640403641 is a deficient number, since it is larger than the sum of its proper divisors (1).

13640403641 is an equidigital number, since it uses as much as digits as its factorization.

13640403641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 32.

The spelling of 13640403641 in words is "thirteen billion, six hundred forty million, four hundred three thousand, six hundred forty-one".