1242105305 has 16 divisors (see below), whose sum is σ = 1711542144. Its totient is φ = 847687680.

The previous prime is 1242105301. The next prime is 1242105407. The reversal of 1242105305 is 5035012421.

It is not a de Polignac number, because 1242105305 - 2² = 1242105301 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1242105301) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76712 + ... + 91481.

It is an arithmetic number, because the mean of its divisors is an integer number (106971384).

Almost surely, 2^1242105305 is an apocalyptic number.

It is an amenable number.

1242105305 is a deficient number, since it is larger than the sum of its proper divisors (469436839).

1242105305 is a wasteful number, since it uses less digits than its factorization.

1242105305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168416.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 1242105305 is about 35243.5143678947. The cubic root of 1242105305 is about 1074.9447399032.

Adding to 1242105305 its reverse (5035012421), we get a palindrome (6277117726).

The spelling of 1242105305 in words is "one billion, two hundred forty-two million, one hundred five thousand, three hundred five".