42206645 has 16 divisors (see below), whose sum is σ = 54682992. Its totient is φ = 31088640.

The previous prime is 42206641. The next prime is 42206669. The reversal of 42206645 is 54660224.

It can be written as a sum of positive squares in 8 ways, for example, as 6482116 + 35724529 = 2546^2 + 5977^2 .

It is not a de Polignac number, because 42206645 - 2² = 42206641 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42206641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41159 + ... + 42171.

It is an arithmetic number, because the mean of its divisors is an integer number (3417687).

Almost surely, 2^42206645 is an apocalyptic number.

It is an amenable number.

42206645 is a deficient number, since it is larger than the sum of its proper divisors (12476347).

42206645 is a wasteful number, since it uses less digits than its factorization.

42206645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1672.

The product of its (nonzero) digits is 11520, while the sum is 29.

The square root of 42206645 is about 6496.6641440050. The cubic root of 42206645 is about 348.1718142421.

Adding to 42206645 its reverse (54660224), we get a palindrome (96866869).

The spelling of 42206645 in words is "forty-two million, two hundred six thousand, six hundred forty-five".