20171648 has 64 divisors (see below), whose sum is σ = 47001600. Its totient is φ = 8443392.

The previous prime is 20171647. The next prime is 20171651. The reversal of 20171648 is 84617102.

It is a tau number, because it is divible by the number of its divisors (64).

It is a self number, because there is not a number n which added to its sum of digits gives 20171648.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20171647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41873 + ... + 42351.

It is an arithmetic number, because the mean of its divisors is an integer number (734400).

Almost surely, 2^20171648 is an apocalyptic number.

20171648 is a gapful number since it is divisible by the number (28) 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 20171648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23500800).

20171648 is an abundant number, since it is smaller than the sum of its proper divisors (26829952).

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

20171648 is an equidigital number, since it uses as much as digits as its factorization.

20171648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 547 (or 535 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 20171648 is about 4491.2857847169. The cubic root of 20171648 is about 272.2160912559.

The spelling of 20171648 in words is "twenty million, one hundred seventy-one thousand, six hundred forty-eight".