166561928 has 48 divisors (see below), whose sum is σ = 341853540. Its totient is φ = 75628800.

The previous prime is 166561873. The next prime is 166561939. The reversal of 166561928 is 829165661.

It can be written as a sum of positive squares in 6 ways, for example, as 128097124 + 38464804 = 11318^2 + 6202^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1060826 + ... + 1060982.

Almost surely, 2^166561928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166561928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (170926770).

166561928 is an abundant number, since it is smaller than the sum of its proper divisors (175291612).

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

166561928 is a wasteful number, since it uses less digits than its factorization.

166561928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 378 (or 273 counting only the distinct ones).

The product of its digits is 155520, while the sum is 44.

The square root of 166561928 is about 12905.8873387303. The cubic root of 166561928 is about 550.2059041730.

The spelling of 166561928 in words is "one hundred sixty-six million, five hundred sixty-one thousand, nine hundred twenty-eight".