166638573 has 16 divisors (see below), whose sum is σ = 261394560. Its totient is φ = 104557248.

The previous prime is 166638551. The next prime is 166638583. The reversal of 166638573 is 375836661.

It is not a de Polignac number, because 166638573 - 2⁸ = 166638317 is a prime.

It is a super-2 number, since 2×166638573² = 55536828022952658, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166638583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 181065 + ... + 181982.

It is an arithmetic number, because the mean of its divisors is an integer number (16337160).

Almost surely, 2^166638573 is an apocalyptic number.

It is an amenable number.

166638573 is a deficient number, since it is larger than the sum of its proper divisors (94755987).

166638573 is a wasteful number, since it uses less digits than its factorization.

166638573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363073 (or 363067 counting only the distinct ones).

The product of its digits is 544320, while the sum is 45.

The square root of 166638573 is about 12908.8563784713. The cubic root of 166638573 is about 550.2902853304.

The spelling of 166638573 in words is "one hundred sixty-six million, six hundred thirty-eight thousand, five hundred seventy-three".