20171124 has 54 divisors (see below), whose sum is σ = 53128530. Its totient is φ = 6445152.

The previous prime is 20171101. The next prime is 20171147. The reversal of 20171124 is 42117102.

It is an interprime number because it is at equal distance from previous prime (20171101) and next prime (20171147).

It can be written as a sum of positive squares in only one way, i.e., 17388900 + 2782224 = 4170^2 + 1668^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20171097 and 20171106.

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 17 ways as a sum of consecutive naturals, for example, 145047 + ... + 145185.

Almost surely, 2^20171124 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20171124, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26564265).

20171124 is an abundant number, since it is smaller than the sum of its proper divisors (32957406).

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

20171124 is a wasteful number, since it uses less digits than its factorization.

20171124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317 (or 173 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 20171124 is about 4491.2274491502. The cubic root of 20171124 is about 272.2137341114.

Adding to 20171124 its reverse (42117102), we get a palindrome (62288226).

The spelling of 20171124 in words is "twenty million, one hundred seventy-one thousand, one hundred twenty-four".