42551509 has 16 divisors (see below), whose sum is σ = 57133440. Its totient is φ = 30605760.

The previous prime is 42551501. The next prime is 42551513. The reversal of 42551509 is 90515524.

It is a cyclic number.

It is not a de Polignac number, because 42551509 - 2³ = 42551501 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42551501) 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 in 15 ways as a sum of consecutive naturals, for example, 20254 + ... + 22255.

It is an arithmetic number, because the mean of its divisors is an integer number (3570840).

Almost surely, 2^42551509 is an apocalyptic number.

It is an amenable number.

42551509 is a deficient number, since it is larger than the sum of its proper divisors (14581931).

42551509 is a wasteful number, since it uses less digits than its factorization.

42551509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42540.

The product of its (nonzero) digits is 9000, while the sum is 31.

The square root of 42551509 is about 6523.1517688921. The cubic root of 42551509 is about 349.1175292377.

The spelling of 42551509 in words is "forty-two million, five hundred fifty-one thousand, five hundred nine".