163276561 has 4 divisors (see below), whose sum is σ = 186601792. Its totient is φ = 139951332.

The previous prime is 163276559. The next prime is 163276571. The reversal of 163276561 is 165672361.

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.

It is a cyclic number.

It is not a de Polignac number, because 163276561 - 2¹ = 163276559 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 163276561.

It is not an unprimeable number, because it can be changed into a prime (163276571) 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, 11662605 + ... + 11662618.

It is an arithmetic number, because the mean of its divisors is an integer number (46650448).

Almost surely, 2^163276561 is an apocalyptic number.

It is an amenable number.

163276561 is a deficient number, since it is larger than the sum of its proper divisors (23325231).

163276561 is an equidigital number, since it uses as much as digits as its factorization.

163276561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23325230.

The product of its digits is 45360, while the sum is 37.

The square root of 163276561 is about 12777.9717091563. The cubic root of 163276561 is about 546.5643252714.

The spelling of 163276561 in words is "one hundred sixty-three million, two hundred seventy-six thousand, five hundred sixty-one".