1242041221 has 4 divisors (see below), whose sum is σ = 1242313600. Its totient is φ = 1241768844.

The previous prime is 1242041219. The next prime is 1242041231. The reversal of 1242041221 is 1221402421.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1242041221 - 2¹ = 1242041219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1242041231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 129231 + ... + 138508.

It is an arithmetic number, because the mean of its divisors is an integer number (310578400).

Almost surely, 2^1242041221 is an apocalyptic number.

It is an amenable number.

1242041221 is a deficient number, since it is larger than the sum of its proper divisors (272379).

1242041221 is an equidigital number, since it uses as much as digits as its factorization.

1242041221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272378.

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

The square root of 1242041221 is about 35242.6051959840. The cubic root of 1242041221 is about 1074.9262530264.

Adding to 1242041221 its reverse (1221402421), we get a palindrome (2463443642).

The spelling of 1242041221 in words is "one billion, two hundred forty-two million, forty-one thousand, two hundred twenty-one".