42737221 has 4 divisors (see below), whose sum is σ = 42852172. Its totient is φ = 42622272.

The previous prime is 42737209. The next prime is 42737231. The reversal of 42737221 is 12273724.

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 33189121 + 9548100 = 5761^2 + 3090^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42737221 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 42737221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42737231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56916 + ... + 57661.

It is an arithmetic number, because the mean of its divisors is an integer number (10713043).

Almost surely, 2^42737221 is an apocalyptic number.

It is an amenable number.

42737221 is a deficient number, since it is larger than the sum of its proper divisors (114951).

42737221 is a wasteful number, since it uses less digits than its factorization.

42737221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114950.

The product of its digits is 4704, while the sum is 28.

The square root of 42737221 is about 6537.3711077160. The cubic root of 42737221 is about 349.6246888476.

The spelling of 42737221 in words is "forty-two million, seven hundred thirty-seven thousand, two hundred twenty-one".