263984161 has 4 divisors (see below), whose sum is σ = 301696192. Its totient is φ = 226272132.

The previous prime is 263984153. The next prime is 263984173. The reversal of 263984161 is 161489362.

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: 161489362 = 2 ⋅80744681.

It is a cyclic number.

It is not a de Polignac number, because 263984161 - 2³ = 263984153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (263984111) 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 3 ways as a sum of consecutive naturals, for example, 18856005 + ... + 18856018.

It is an arithmetic number, because the mean of its divisors is an integer number (75424048).

Almost surely, 2^263984161 is an apocalyptic number.

It is an amenable number.

263984161 is a deficient number, since it is larger than the sum of its proper divisors (37712031).

263984161 is an equidigital number, since it uses as much as digits as its factorization.

263984161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37712030.

The product of its digits is 62208, while the sum is 40.

The square root of 263984161 is about 16247.5893904296. The cubic root of 263984161 is about 641.4940364152.

The spelling of 263984161 in words is "two hundred sixty-three million, nine hundred eighty-four thousand, one hundred sixty-one".