661656055 has 8 divisors (see below), whose sum is σ = 794171232. Its totient is φ = 529202208.

The previous prime is 661656053. The next prime is 661656071. The reversal of 661656055 is 550656166.

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

It is a cyclic number.

It is not a de Polignac number, because 661656055 - 2¹ = 661656053 is a prime.

It is a super-4 number, since 4×661656055⁴ (a number of 36 digits) contains 4444 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 661655999 and 661656017.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661656053) 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, 13254 + ... + 38716.

It is an arithmetic number, because the mean of its divisors is an integer number (99271404).

Almost surely, 2^661656055 is an apocalyptic number.

661656055 is a deficient number, since it is larger than the sum of its proper divisors (132515177).

661656055 is a wasteful number, since it uses less digits than its factorization.

661656055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30665.

The product of its (nonzero) digits is 162000, while the sum is 40.

The square root of 661656055 is about 25722.6758911277. The cubic root of 661656055 is about 871.3863724143.

The spelling of 661656055 in words is "six hundred sixty-one million, six hundred fifty-six thousand, fifty-five".