163640475637 has 2 divisors, whose sum is σ = 163640475638. Its totient is φ = 163640475636.

The previous prime is 163640475617. The next prime is 163640475671. The reversal of 163640475637 is 736574046361.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 102855545521 + 60784930116 = 320711^2 + 246546^2 .

It is a cyclic number.

It is not a de Polignac number, because 163640475637 - 2¹¹ = 163640473589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (163640475617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81820237818 + 81820237819.

It is an arithmetic number, because the mean of its divisors is an integer number (81820237819).

Almost surely, 2^163640475637 is an apocalyptic number.

It is an amenable number.

163640475637 is a deficient number, since it is larger than the sum of its proper divisors (1).

163640475637 is an equidigital number, since it uses as much as digits as its factorization.

163640475637 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7620480, while the sum is 52.

The spelling of 163640475637 in words is "one hundred sixty-three billion, six hundred forty million, four hundred seventy-five thousand, six hundred thirty-seven".