42688817 has 2 divisors, whose sum is σ = 42688818. Its totient is φ = 42688816.

The previous prime is 42688813. The next prime is 42688843. The reversal of 42688817 is 71888624.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27133681 + 15555136 = 5209^2 + 3944^2 .

It is a cyclic number.

It is not a de Polignac number, because 42688817 - 2² = 42688813 is a prime.

It is a super-3 number, since 3×42688817³ (a number of 24 digits) contains 333 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (42688813) 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 as a sum of consecutive naturals, namely, 21344408 + 21344409.

It is an arithmetic number, because the mean of its divisors is an integer number (21344409).

Almost surely, 2^42688817 is an apocalyptic number.

It is an amenable number.

42688817 is a deficient number, since it is larger than the sum of its proper divisors (1).

42688817 is an equidigital number, since it uses as much as digits as its factorization.

42688817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 172032, while the sum is 44.

The square root of 42688817 is about 6533.6679591176. The cubic root of 42688817 is about 349.4926444912.

The spelling of 42688817 in words is "forty-two million, six hundred eighty-eight thousand, eight hundred seventeen".