42420289 has 4 divisors (see below), whose sum is σ = 42744240. Its totient is φ = 42096340.

The previous prime is 42420271. The next prime is 42420311. The reversal of 42420289 is 98202424.

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 a de Polignac number, because none of the positive numbers 2^k-42420289 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 42420289.

It is not an unprimeable number, because it can be changed into a prime (42420229) 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, 161779 + ... + 162040.

It is an arithmetic number, because the mean of its divisors is an integer number (10686060).

Almost surely, 2^42420289 is an apocalyptic number.

It is an amenable number.

42420289 is a deficient number, since it is larger than the sum of its proper divisors (323951).

42420289 is a wasteful number, since it uses less digits than its factorization.

42420289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323950.

The product of its (nonzero) digits is 9216, while the sum is 31.

The square root of 42420289 is about 6513.0859813148. The cubic root of 42420289 is about 348.7582911061.

The spelling of 42420289 in words is "forty-two million, four hundred twenty thousand, two hundred eighty-nine".