1242402121 has 4 divisors (see below), whose sum is σ = 1242685332. Its totient is φ = 1242118912.

The previous prime is 1242402101. The next prime is 1242402127. The reversal of 1242402121 is 1212042421.

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 1096934400 + 145467721 = 33120^2 + 12061^2 .

It is a cyclic number.

It is not a de Polignac number, because 1242402121 - 2²⁷ = 1108184393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1242402127) 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, 134920 + ... + 143833.

It is an arithmetic number, because the mean of its divisors is an integer number (310671333).

Almost surely, 2^1242402121 is an apocalyptic number.

It is an amenable number.

1242402121 is a deficient number, since it is larger than the sum of its proper divisors (283211).

1242402121 is an equidigital number, since it uses as much as digits as its factorization.

1242402121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 283210.

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 1242402121 is about 35247.7250471573. The cubic root of 1242402121 is about 1075.0303567415.

Adding to 1242402121 its reverse (1212042421), we get a palindrome (2454444542).

The spelling of 1242402121 in words is "one billion, two hundred forty-two million, four hundred two thousand, one hundred twenty-one".