42215561 has 8 divisors (see below), whose sum is σ = 44325120. Its totient is φ = 40149648.

The previous prime is 42215531. The next prime is 42215581. The reversal of 42215561 is 16551224.

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

It is a cyclic number.

It is not a de Polignac number, because 42215561 - 2⁶ = 42215497 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 42215561.

It is not an unprimeable number, because it can be changed into a prime (42215531) 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, 8921 + ... + 12806.

It is an arithmetic number, because the mean of its divisors is an integer number (5540640).

Almost surely, 2^42215561 is an apocalyptic number.

It is an amenable number.

42215561 is a deficient number, since it is larger than the sum of its proper divisors (2109559).

42215561 is a wasteful number, since it uses less digits than its factorization.

42215561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21823.

The product of its digits is 2400, while the sum is 26.

The square root of 42215561 is about 6497.3503060863. The cubic root of 42215561 is about 348.1963291917.

Adding to 42215561 its reverse (16551224), we get a palindrome (58766785).

The spelling of 42215561 in words is "forty-two million, two hundred fifteen thousand, five hundred sixty-one".