163243661 has 4 divisors (see below), whose sum is σ = 186564192. Its totient is φ = 139923132.

The previous prime is 163243651. The next prime is 163243681. The reversal of 163243661 is 166342361.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 166342361 = 43 ⋅3868427.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-163243661 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 (163243601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11660255 + ... + 11660268.

It is an arithmetic number, because the mean of its divisors is an integer number (46641048).

Almost surely, 2^163243661 is an apocalyptic number.

It is an amenable number.

163243661 is a deficient number, since it is larger than the sum of its proper divisors (23320531).

163243661 is an equidigital number, since it uses as much as digits as its factorization.

163243661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23320530.

The product of its digits is 15552, while the sum is 32.

The square root of 163243661 is about 12776.6842725333. The cubic root of 163243661 is about 546.5276121549.

The spelling of 163243661 in words is "one hundred sixty-three million, two hundred forty-three thousand, six hundred sixty-one".