42409665 has 12 divisors (see below), whose sum is σ = 73510164. Its totient is φ = 22618464.

The previous prime is 42409663. The next prime is 42409673. The reversal of 42409665 is 56690424.

It can be written as a sum of positive squares in 2 ways, for example, as 10870209 + 31539456 = 3297^2 + 5616^2 .

It is not a de Polignac number, because 42409665 - 2¹ = 42409663 is a prime.

It is not an unprimeable number, because it can be changed into a prime (42409663) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 471174 + ... + 471263.

It is an arithmetic number, because the mean of its divisors is an integer number (6125847).

Almost surely, 2^42409665 is an apocalyptic number.

42409665 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

42409665 is a deficient number, since it is larger than the sum of its proper divisors (31100499).

42409665 is a wasteful number, since it uses less digits than its factorization.

42409665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 942448 (or 942445 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 42409665 is about 6512.2703414401. The cubic root of 42409665 is about 348.7291736128.

The spelling of 42409665 in words is "forty-two million, four hundred nine thousand, six hundred sixty-five".