42640205 has 8 divisors (see below), whose sum is σ = 52416504. Its totient is φ = 33280000.

The previous prime is 42640201. The next prime is 42640217. The reversal of 42640205 is 50204624.

It can be written as a sum of positive squares in 4 ways, for example, as 2735716 + 39904489 = 1654^2 + 6317^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 42640205 - 2² = 42640201 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42640201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 103796 + ... + 104205.

It is an arithmetic number, because the mean of its divisors is an integer number (6552063).

Almost surely, 2^42640205 is an apocalyptic number.

It is an amenable number.

42640205 is a deficient number, since it is larger than the sum of its proper divisors (9776299).

42640205 is a wasteful number, since it uses less digits than its factorization.

42640205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208047.

The product of its (nonzero) digits is 1920, while the sum is 23.

The square root of 42640205 is about 6529.9467838567. The cubic root of 42640205 is about 349.3599322208.

Adding to 42640205 its reverse (50204624), we get a palindrome (92844829).

The spelling of 42640205 in words is "forty-two million, six hundred forty thousand, two hundred five".