221765169 has 16 divisors (see below), whose sum is σ = 313244480. Its totient is φ = 139164480.

The previous prime is 221765143. The next prime is 221765171. The reversal of 221765169 is 961567122.

It is not a de Polignac number, because 221765169 - 2²³ = 213376561 is a prime.

It is a super-2 number, since 2×221765169² = 98359580363197122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221765179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3442 + ... + 21339.

It is an arithmetic number, because the mean of its divisors is an integer number (19577780).

Almost surely, 2^221765169 is an apocalyptic number.

It is an amenable number.

221765169 is a deficient number, since it is larger than the sum of its proper divisors (91479311).

221765169 is a wasteful number, since it uses less digits than its factorization.

221765169 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24960.

The product of its digits is 45360, while the sum is 39.

The square root of 221765169 is about 14891.7819282986. The cubic root of 221765169 is about 605.2913188464.

The spelling of 221765169 in words is "two hundred twenty-one million, seven hundred sixty-five thousand, one hundred sixty-nine".