1242123105 has 64 divisors (see below), whose sum is σ = 2175102720. Its totient is φ = 602873856.

The previous prime is 1242123101. The next prime is 1242123109. The reversal of 1242123105 is 5013212421.

It is an interprime number because it is at equal distance from previous prime (1242123101) and next prime (1242123109).

It is not a de Polignac number, because 1242123105 - 2² = 1242123101 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1242123101) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 985966 + ... + 987224.

It is an arithmetic number, because the mean of its divisors is an integer number (33985980).

Almost surely, 2^1242123105 is an apocalyptic number.

1242123105 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1242123105 is a deficient number, since it is larger than the sum of its proper divisors (932979615).

1242123105 is a wasteful number, since it uses less digits than its factorization.

1242123105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1410.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 1242123105 is about 35243.7668957221. The cubic root of 1242123105 is about 1074.9498747134.

Adding to 1242123105 its reverse (5013212421), we get a palindrome (6255335526).

The spelling of 1242123105 in words is "one billion, two hundred forty-two million, one hundred twenty-three thousand, one hundred five".