1230021305 has 4 divisors (see below), whose sum is σ = 1476025572. Its totient is φ = 984017040.

The previous prime is 1230021277. The next prime is 1230021307. The reversal of 1230021305 is 5031200321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5031200321 = 7 ⋅718742903.

It can be written as a sum of positive squares in 2 ways, for example, as 739132969 + 490888336 = 27187^2 + 22156^2 .

It is not a de Polignac number, because 1230021305 - 2⁸ = 1230021049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1230021307) 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, 123002126 + ... + 123002135.

It is an arithmetic number, because the mean of its divisors is an integer number (369006393).

Almost surely, 2^1230021305 is an apocalyptic number.

It is an amenable number.

1230021305 is a deficient number, since it is larger than the sum of its proper divisors (246004267).

1230021305 is an equidigital number, since it uses as much as digits as its factorization.

1230021305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246004266.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 1230021305 is about 35071.6595700859. The cubic root of 1230021305 is about 1071.4474558492.

Adding to 1230021305 its reverse (5031200321), we get a palindrome (6261221626).

The spelling of 1230021305 in words is "one billion, two hundred thirty million, twenty-one thousand, three hundred five".