75664209 has 4 divisors (see below), whose sum is σ = 100885616. Its totient is φ = 50442804.

The previous prime is 75664207. The next prime is 75664241. The reversal of 75664209 is 90246657.

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: 90246657 = 3 ⋅30082219.

It is not a de Polignac number, because 75664209 - 2¹ = 75664207 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (75664207) 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, 12610699 + ... + 12610704.

It is an arithmetic number, because the mean of its divisors is an integer number (25221404).

Almost surely, 2^75664209 is an apocalyptic number.

It is an amenable number.

75664209 is a deficient number, since it is larger than the sum of its proper divisors (25221407).

75664209 is a wasteful number, since it uses less digits than its factorization.

75664209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25221406.

The product of its (nonzero) digits is 90720, while the sum is 39.

The square root of 75664209 is about 8698.5176323325. The cubic root of 75664209 is about 422.9575990451.

The spelling of 75664209 in words is "seventy-five million, six hundred sixty-four thousand, two hundred nine".