42665993 has 4 divisors (see below), whose sum is σ = 42707268. Its totient is φ = 42624720.

The previous prime is 42665957. The next prime is 42666053. The reversal of 42665993 is 39956624.

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 23551609 + 19114384 = 4853^2 + 4372^2 .

It is a cyclic number.

It is not a de Polignac number, because 42665993 - 2¹⁶ = 42600457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42665923) 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, 19046 + ... + 21167.

It is an arithmetic number, because the mean of its divisors is an integer number (10676817).

Almost surely, 2^42665993 is an apocalyptic number.

It is an amenable number.

42665993 is a deficient number, since it is larger than the sum of its proper divisors (41275).

42665993 is a wasteful number, since it uses less digits than its factorization.

42665993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41274.

The product of its digits is 349920, while the sum is 44.

The square root of 42665993 is about 6531.9210803561. The cubic root of 42665993 is about 349.4303468160.

The spelling of 42665993 in words is "forty-two million, six hundred sixty-five thousand, nine hundred ninety-three".