166243428 has 120 divisors (see below), whose sum is σ = 484517880. Its totient is φ = 49351680.

The previous prime is 166243409. The next prime is 166243433. The reversal of 166243428 is 824342661.

166243428 is a `hidden beast` number, since 1 + 6 + 624 + 3 + 4 + 28 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 142884 + 166100544 = 378^2 + 12888^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 166243392 and 166243401.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 121468 + ... + 122828.

It is an arithmetic number, because the mean of its divisors is an integer number (4037649).

Almost surely, 2^166243428 is an apocalyptic number.

166243428 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 166243428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (242258940).

166243428 is an abundant number, since it is smaller than the sum of its proper divisors (318274452).

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

166243428 is a wasteful number, since it uses less digits than its factorization.

166243428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1419 (or 1408 counting only the distinct ones).

The product of its digits is 55296, while the sum is 36.

The square root of 166243428 is about 12893.5421044801. The cubic root of 166243428 is about 549.8549788448.

The spelling of 166243428 in words is "one hundred sixty-six million, two hundred forty-three thousand, four hundred twenty-eight".