42688091 has 4 divisors (see below), whose sum is σ = 42720384. Its totient is φ = 42655800.

The previous prime is 42688057. The next prime is 42688109. The reversal of 42688091 is 19088624.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 42688091 - 2¹⁰ = 42687067 is a prime.

It is a super-3 number, since 3×42688091³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42688021) 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, 14075 + ... + 16836.

It is an arithmetic number, because the mean of its divisors is an integer number (10680096).

Almost surely, 2^42688091 is an apocalyptic number.

42688091 is a deficient number, since it is larger than the sum of its proper divisors (32293).

42688091 is a wasteful number, since it uses less digits than its factorization.

42688091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32292.

The product of its (nonzero) digits is 27648, while the sum is 38.

The square root of 42688091 is about 6533.6124005025. The cubic root of 42688091 is about 349.4906632299.

The spelling of 42688091 in words is "forty-two million, six hundred eighty-eight thousand, ninety-one".