166581655464 has 128 divisors (see below), whose sum is σ = 495903744000. Its totient is φ = 45622773504.

The previous prime is 166581655463. The next prime is 166581655483. The reversal of 166581655464 is 464556185661.

It is not an unprimeable number, because it can be changed into a prime (166581655463) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 554217 + ... + 800199.

It is an arithmetic number, because the mean of its divisors is an integer number (3874248000).

Almost surely, 2^166581655464 is an apocalyptic number.

166581655464 is a gapful number since it is divisible by the number (14) 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 166581655464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (247951872000).

166581655464 is an abundant number, since it is smaller than the sum of its proper divisors (329322088536).

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

166581655464 is a wasteful number, since it uses less digits than its factorization.

166581655464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246167 (or 246163 counting only the distinct ones).

The product of its digits is 20736000, while the sum is 57.

The spelling of 166581655464 in words is "one hundred sixty-six billion, five hundred eighty-one million, six hundred fifty-five thousand, four hundred sixty-four".