166378553 has 8 divisors (see below), whose sum is σ = 182176896. Its totient is φ = 150692400.

The previous prime is 166378549. The next prime is 166378559. The reversal of 166378553 is 355873661.

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 166378553 - 2² = 166378549 is a prime.

It is not an unprimeable number, because it can be changed into a prime (166378559) 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, 24926 + ... + 30887.

It is an arithmetic number, because the mean of its divisors is an integer number (22772112).

Almost surely, 2^166378553 is an apocalyptic number.

It is an amenable number.

166378553 is a deficient number, since it is larger than the sum of its proper divisors (15798343).

166378553 is a wasteful number, since it uses less digits than its factorization.

166378553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56095.

The product of its digits is 453600, while the sum is 44.

The square root of 166378553 is about 12898.7810664419. The cubic root of 166378553 is about 550.0039151236.

The spelling of 166378553 in words is "one hundred sixty-six million, three hundred seventy-eight thousand, five hundred fifty-three".