42240217 has 4 divisors (see below), whose sum is σ = 42870736. Its totient is φ = 41609700.

The previous prime is 42240181. The next prime is 42240221. The reversal of 42240217 is 71204224.

It is a happy number.

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 42240217 - 2⁷ = 42240089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42240017) 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, 315159 + ... + 315292.

It is an arithmetic number, because the mean of its divisors is an integer number (10717684).

Almost surely, 2^42240217 is an apocalyptic number.

It is an amenable number.

42240217 is a deficient number, since it is larger than the sum of its proper divisors (630519).

42240217 is an equidigital number, since it uses as much as digits as its factorization.

42240217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 630518.

The product of its (nonzero) digits is 896, while the sum is 22.

The square root of 42240217 is about 6499.2474179708. The cubic root of 42240217 is about 348.2641040252.

The spelling of 42240217 in words is "forty-two million, two hundred forty thousand, two hundred seventeen".