56661009 has 8 divisors (see below), whose sum is σ = 76786752. Its totient is φ = 37154640.

The previous prime is 56661001. The next prime is 56661013. The reversal of 56661009 is 90016665.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 56661009 - 2³ = 56661001 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (56661001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 154629 + ... + 154994.

It is an arithmetic number, because the mean of its divisors is an integer number (9598344).

Almost surely, 2^56661009 is an apocalyptic number.

It is an amenable number.

56661009 is a deficient number, since it is larger than the sum of its proper divisors (20125743).

56661009 is a wasteful number, since it uses less digits than its factorization.

56661009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309687.

The product of its (nonzero) digits is 9720, while the sum is 33.

The square root of 56661009 is about 7527.3507291742. The cubic root of 56661009 is about 384.0856674645.

The spelling of 56661009 in words is "fifty-six million, six hundred sixty-one thousand, nine".