166387440 has 80 divisors (see below), whose sum is σ = 522921888. Its totient is φ = 43757568.

The previous prime is 166387439. The next prime is 166387453. The reversal of 166387440 is 44783661.

166387440 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 12772 + ... + 22268.

Almost surely, 2^166387440 is an apocalyptic number.

166387440 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 166387440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (261460944).

166387440 is an abundant number, since it is smaller than the sum of its proper divisors (356534448).

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

166387440 is a wasteful number, since it uses less digits than its factorization.

166387440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9586 (or 9580 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 39.

The square root of 166387440 is about 12899.1255517574. The cubic root of 166387440 is about 550.0137076473.

The spelling of 166387440 in words is "one hundred sixty-six million, three hundred eighty-seven thousand, four hundred forty".