42321209 has 4 divisors (see below), whose sum is σ = 48367104. Its totient is φ = 36275316.

The previous prime is 42321203. The next prime is 42321241. The reversal of 42321209 is 90212324.

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 42321209 - 2⁴ = 42321193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42321203) 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, 3022937 + ... + 3022950.

It is an arithmetic number, because the mean of its divisors is an integer number (12091776).

Almost surely, 2^42321209 is an apocalyptic number.

It is an amenable number.

42321209 is a deficient number, since it is larger than the sum of its proper divisors (6045895).

42321209 is an equidigital number, since it uses as much as digits as its factorization.

42321209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6045894.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 42321209 is about 6505.4753093068. The cubic root of 42321209 is about 348.4865507799.

The spelling of 42321209 in words is "forty-two million, three hundred twenty-one thousand, two hundred nine".