42889987 has 16 divisors (see below), whose sum is σ = 49911552. Its totient is φ = 36099360.

The previous prime is 42889883. The next prime is 42889999. The reversal of 42889987 is 78998824.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42889987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42889087) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 129412 + ... + 129742.

It is an arithmetic number, because the mean of its divisors is an integer number (3119472).

Almost surely, 2^42889987 is an apocalyptic number.

42889987 is a deficient number, since it is larger than the sum of its proper divisors (7021565).

42889987 is a wasteful number, since it uses less digits than its factorization.

42889987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 618.

The product of its digits is 2322432, while the sum is 55.

The square root of 42889987 is about 6549.0447395021. The cubic root of 42889987 is about 350.0407762016.

It can be divided in two parts, 428 and 89987, that multiplied together give a square (38514436 = 6206²).

The spelling of 42889987 in words is "forty-two million, eight hundred eighty-nine thousand, nine hundred eighty-seven".