1242203421 has 4 divisors (see below), whose sum is σ = 1656271232. Its totient is φ = 828135612.

The previous prime is 1242203399. The next prime is 1242203423. The reversal of 1242203421 is 1243022421.

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 not a de Polignac number, because 1242203421 - 2⁹ = 1242202909 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 (1242203423) 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, 207033901 + ... + 207033906.

It is an arithmetic number, because the mean of its divisors is an integer number (414067808).

Almost surely, 2^1242203421 is an apocalyptic number.

It is an amenable number.

1242203421 is a deficient number, since it is larger than the sum of its proper divisors (414067811).

1242203421 is an equidigital number, since it uses as much as digits as its factorization.

1242203421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414067810.

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 1242203421 is about 35244.9063128277. The cubic root of 1242203421 is about 1074.9730430594.

Adding to 1242203421 its reverse (1243022421), we get a palindrome (2485225842).

The spelling of 1242203421 in words is "one billion, two hundred forty-two million, two hundred three thousand, four hundred twenty-one".