42820417 has 4 divisors (see below), whose sum is σ = 42890436. Its totient is φ = 42750400.

The previous prime is 42820409. The next prime is 42820423. The reversal of 42820417 is 71402824.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12173121 + 30647296 = 3489^2 + 5536^2 .

It is a cyclic number.

It is not a de Polignac number, because 42820417 - 2³ = 42820409 is a prime.

It is a super-2 number, since 2×42820417² = 3667176224107778, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42824417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34084 + ... + 35317.

It is an arithmetic number, because the mean of its divisors is an integer number (10722609).

Almost surely, 2^42820417 is an apocalyptic number.

It is an amenable number.

42820417 is a deficient number, since it is larger than the sum of its proper divisors (70019).

42820417 is an equidigital number, since it uses as much as digits as its factorization.

42820417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70018.

The product of its (nonzero) digits is 3584, while the sum is 28.

The square root of 42820417 is about 6543.7311222268. The cubic root of 42820417 is about 349.8514117575.

The spelling of 42820417 in words is "forty-two million, eight hundred twenty thousand, four hundred seventeen".