42020945 has 4 divisors (see below), whose sum is σ = 50425140. Its totient is φ = 33616752.

The previous prime is 42020939. The next prime is 42020959. The reversal of 42020945 is 54902024.

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 13366336 + 28654609 = 3656^2 + 5353^2 .

It is a cyclic number.

It is not a de Polignac number, because 42020945 - 2⁴ = 42020929 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4202090 + ... + 4202099.

It is an arithmetic number, because the mean of its divisors is an integer number (12606285).

Almost surely, 2^42020945 is an apocalyptic number.

It is an amenable number.

42020945 is a deficient number, since it is larger than the sum of its proper divisors (8404195).

42020945 is an equidigital number, since it uses as much as digits as its factorization.

42020945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8404194.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 42020945 is about 6482.3564388269. The cubic root of 42020945 is about 347.6604369323.

Adding to 42020945 its reverse (54902024), we get a palindrome (96922969).

The spelling of 42020945 in words is "forty-two million, twenty thousand, nine hundred forty-five".