166856640 has 112 divisors (see below), whose sum is σ = 533278080. Its totient is φ = 44200960.

The previous prime is 166856621. The next prime is 166856647. The reversal of 166856640 is 46658661.

It is a super-2 number, since 2×166856640² = 55682276624179200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 166856592 and 166856601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166856647) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 171355 + ... + 172325.

Almost surely, 2^166856640 is an apocalyptic number.

166856640 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 166856640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (266639040).

166856640 is an abundant number, since it is smaller than the sum of its proper divisors (366421440).

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

166856640 is a wasteful number, since it uses less digits than its factorization.

166856640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1170 (or 1160 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 42.

The square root of 166856640 is about 12917.3000274825. The cubic root of 166856640 is about 550.5302214639.

The spelling of 166856640 in words is "one hundred sixty-six million, eight hundred fifty-six thousand, six hundred forty".