166353220 has 72 divisors (see below), whose sum is σ = 391533912. Its totient is φ = 59304960.

The previous prime is 166353217. The next prime is 166353241. The reversal of 166353220 is 22353661.

It can be written as a sum of positive squares in 4 ways, for example, as 85784644 + 80568576 = 9262^2 + 8976^2 .

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 127612 + ... + 128908.

It is an arithmetic number, because the mean of its divisors is an integer number (5437971).

Almost surely, 2^166353220 is an apocalyptic number.

166353220 is a gapful number since it is divisible by the number (10) 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 166353220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (195766956).

166353220 is an abundant number, since it is smaller than the sum of its proper divisors (225180692).

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

166353220 is a wasteful number, since it uses less digits than its factorization.

166353220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1381 (or 1368 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 28.

The square root of 166353220 is about 12897.7990370450. The cubic root of 166353220 is about 549.9759989527.

It can be divided in two parts, 1663 and 53220, that multiplied together give a triangular number (88504860 = T₁₃₃₀₄).

The spelling of 166353220 in words is "one hundred sixty-six million, three hundred fifty-three thousand, two hundred twenty".