42042661 has 4 divisors (see below), whose sum is σ = 42059500. Its totient is φ = 42025824.

The previous prime is 42042659. The next prime is 42042673. The reversal of 42042661 is 16624024.

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 24453025 + 17589636 = 4945^2 + 4194^2 .

It is a cyclic number.

It is not a de Polignac number, because 42042661 - 2¹ = 42042659 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 (42042601) 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, 3846 + ... + 9943.

It is an arithmetic number, because the mean of its divisors is an integer number (10514875).

Almost surely, 2^42042661 is an apocalyptic number.

It is an amenable number.

42042661 is a deficient number, since it is larger than the sum of its proper divisors (16839).

42042661 is a wasteful number, since it uses less digits than its factorization.

42042661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16838.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 42042661 is about 6484.0312306466. The cubic root of 42042661 is about 347.7203157528.

Adding to 42042661 its reverse (16624024), we get a palindrome (58666685).

The spelling of 42042661 in words is "forty-two million, forty-two thousand, six hundred sixty-one".