56665409 has 4 divisors (see below), whose sum is σ = 57871104. Its totient is φ = 55459716.

The previous prime is 56665397. The next prime is 56665423. The reversal of 56665409 is 90456665.

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.

It is a cyclic number.

It is not a de Polignac number, because 56665409 - 2²⁴ = 39888193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (56665309) 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, 602777 + ... + 602870.

It is an arithmetic number, because the mean of its divisors is an integer number (14467776).

Almost surely, 2^56665409 is an apocalyptic number.

It is an amenable number.

56665409 is a deficient number, since it is larger than the sum of its proper divisors (1205695).

56665409 is a wasteful number, since it uses less digits than its factorization.

56665409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1205694.

The product of its (nonzero) digits is 194400, while the sum is 41.

The square root of 56665409 is about 7527.6429910032. The cubic root of 56665409 is about 384.0956092406.

The spelling of 56665409 in words is "fifty-six million, six hundred sixty-five thousand, four hundred nine".