166538988 has 144 divisors (see below), whose sum is σ = 532686336. Its totient is φ = 42612480.

The previous prime is 166538951. The next prime is 166538993. The reversal of 166538988 is 889835661.

166538988 is a `hidden beast` number, since 16 + 6 + 538 + 98 + 8 = 666.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 201945 + ... + 202767.

Almost surely, 2^166538988 is an apocalyptic number.

166538988 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166538988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (266343168).

166538988 is an abundant number, since it is smaller than the sum of its proper divisors (366147348).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166538988 is a wasteful number, since it uses less digits than its factorization.

166538988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 924 (or 919 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 54.

The square root of 166538988 is about 12904.9985664470. The cubic root of 166538988 is about 550.1806436926.

The spelling of 166538988 in words is "one hundred sixty-six million, five hundred thirty-eight thousand, nine hundred eighty-eight".