75561009 has 4 divisors (see below), whose sum is σ = 100748016. Its totient is φ = 50374004.

The previous prime is 75560977. The next prime is 75561023. The reversal of 75561009 is 90016557.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90016557 = 3 ⋅30005519.

It is a cyclic number.

It is not a de Polignac number, because 75561009 - 2⁵ = 75560977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (75561709) 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, 12593499 + ... + 12593504.

It is an arithmetic number, because the mean of its divisors is an integer number (25187004).

Almost surely, 2^75561009 is an apocalyptic number.

It is an amenable number.

75561009 is a deficient number, since it is larger than the sum of its proper divisors (25187007).

75561009 is a wasteful number, since it uses less digits than its factorization.

75561009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25187006.

The product of its (nonzero) digits is 9450, while the sum is 33.

The square root of 75561009 is about 8692.5835630151. The cubic root of 75561009 is about 422.7652179773.

The spelling of 75561009 in words is "seventy-five million, five hundred sixty-one thousand, nine".