20181001 has 8 divisors (see below), whose sum is σ = 20674944. Its totient is φ = 19689840.

The previous prime is 20180987. The next prime is 20181019. The reversal of 20181001 is 10018102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20181001 - 2¹¹ = 20178953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20188001) 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, 24171 + ... + 24991.

It is an arithmetic number, because the mean of its divisors is an integer number (2584368).

Almost surely, 2^20181001 is an apocalyptic number.

It is an amenable number.

20181001 is a deficient number, since it is larger than the sum of its proper divisors (493943).

20181001 is an equidigital number, since it uses as much as digits as its factorization.

20181001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1391.

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 20181001 is about 4492.3269026196. The cubic root of 20181001 is about 272.2581576205.

Adding to 20181001 its reverse (10018102), we get a palindrome (30199103).

The spelling of 20181001 in words is "twenty million, one hundred eighty-one thousand, one".