1220081165 has 4 divisors (see below), whose sum is σ = 1464097404. Its totient is φ = 976064928.

The previous prime is 1220081141. The next prime is 1220081201. The reversal of 1220081165 is 5611800221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 569729161 + 650352004 = 23869^2 + 25502^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220081165 - 2⁶ = 1220081101 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122008112 + ... + 122008121.

It is an arithmetic number, because the mean of its divisors is an integer number (366024351).

Almost surely, 2^1220081165 is an apocalyptic number.

It is an amenable number.

1220081165 is a deficient number, since it is larger than the sum of its proper divisors (244016239).

1220081165 is an equidigital number, since it uses as much as digits as its factorization.

1220081165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244016238.

The product of its (nonzero) digits is 960, while the sum is 26.

The square root of 1220081165 is about 34929.6602474172. The cubic root of 1220081165 is about 1068.5534255839.

Adding to 1220081165 its reverse (5611800221), we get a palindrome (6831881386).

The spelling of 1220081165 in words is "one billion, two hundred twenty million, eighty-one thousand, one hundred sixty-five".