163640643 has 8 divisors (see below), whose sum is σ = 219906048. Its totient is φ = 108234504.

The previous prime is 163640641. The next prime is 163640693. The reversal of 163640643 is 346046361.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 163640643 - 2¹ = 163640641 is a prime.

It is not an unprimeable number, because it can be changed into a prime (163640641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 214371 + ... + 215132.

It is an arithmetic number, because the mean of its divisors is an integer number (27488256).

Almost surely, 2^163640643 is an apocalyptic number.

163640643 is a deficient number, since it is larger than the sum of its proper divisors (56265405).

163640643 is a wasteful number, since it uses less digits than its factorization.

163640643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429633.

The product of its (nonzero) digits is 31104, while the sum is 33.

The square root of 163640643 is about 12792.2102468651. The cubic root of 163640643 is about 546.9702755712.

The spelling of 163640643 in words is "one hundred sixty-three million, six hundred forty thousand, six hundred forty-three".