220665481 has 4 divisors (see below), whose sum is σ = 220781572. Its totient is φ = 220549392.

The previous prime is 220665463. The next prime is 220665499. The reversal of 220665481 is 184566022.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 184566022 = 2 ⋅92283011.

It is an interprime number because it is at equal distance from previous prime (220665463) and next prime (220665499).

It can be written as a sum of positive squares in 2 ways, for example, as 178623225 + 42042256 = 13365^2 + 6484^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-220665481 is a prime.

It is a super-2 number, since 2×220665481² = 97386509009922722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (220665461) 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, 55146 + ... + 59011.

It is an arithmetic number, because the mean of its divisors is an integer number (55195393).

Almost surely, 2^220665481 is an apocalyptic number.

It is an amenable number.

220665481 is a deficient number, since it is larger than the sum of its proper divisors (116091).

220665481 is a wasteful number, since it uses less digits than its factorization.

220665481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116090.

The product of its (nonzero) digits is 23040, while the sum is 34.

The square root of 220665481 is about 14854.8133949909. The cubic root of 220665481 is about 604.2891553304.

The spelling of 220665481 in words is "two hundred twenty million, six hundred sixty-five thousand, four hundred eighty-one".