166651557 has 8 divisors (see below), whose sum is σ = 226394784. Its totient is φ = 109004688.

The previous prime is 166651553. The next prime is 166651607. The reversal of 166651557 is 755156661.

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

It is not a de Polignac number, because 166651557 - 2² = 166651553 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166651553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 523903 + ... + 524220.

It is an arithmetic number, because the mean of its divisors is an integer number (28299348).

Almost surely, 2^166651557 is an apocalyptic number.

It is an amenable number.

166651557 is a deficient number, since it is larger than the sum of its proper divisors (59743227).

166651557 is a wasteful number, since it uses less digits than its factorization.

166651557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1048179.

The product of its digits is 189000, while the sum is 42.

The square root of 166651557 is about 12909.3592792206. The cubic root of 166651557 is about 550.3045773065.

The spelling of 166651557 in words is "one hundred sixty-six million, six hundred fifty-one thousand, five hundred fifty-seven".