20001023 has 8 divisors (see below), whose sum is σ = 22885920. Its totient is φ = 17123040.

The previous prime is 20001019. The next prime is 20001029. The reversal of 20001023 is 32010002.

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 20001023 - 2² = 20001019 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20001023.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20001029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8633 + ... + 10701.

It is an arithmetic number, because the mean of its divisors is an integer number (2860740).

Almost surely, 2^20001023 is an apocalyptic number.

20001023 is a deficient number, since it is larger than the sum of its proper divisors (2884897).

20001023 is a wasteful number, since it uses less digits than its factorization.

20001023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3457.

The product of its (nonzero) digits is 12, while the sum is 8.

The square root of 20001023 is about 4472.2503284141. The cubic root of 20001023 is about 271.4463896626.

Adding to 20001023 its reverse (32010002), we get a palindrome (52011025).

The spelling of 20001023 in words is "twenty million, one thousand, twenty-three".