20211000 has 64 divisors (see below), whose sum is σ = 63067680. Its totient is φ = 5388800.

The previous prime is 20210963. The next prime is 20211001. The reversal of 20211000 is 11202.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a self number, because there is not a number n which added to its sum of digits gives 20211000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211001) 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 15 ways as a sum of consecutive naturals, for example, 369 + ... + 6368.

Almost surely, 2^20211000 is an apocalyptic number.

20211000 is a gapful number since it is divisible by the number (20) 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 20211000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31533840).

20211000 is an abundant number, since it is smaller than the sum of its proper divisors (42856680).

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

20211000 is a wasteful number, since it uses less digits than its factorization.

20211000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6761 (or 6747 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 6.

The square root of 20211000 is about 4495.6645782353. The cubic root of 20211000 is about 272.3929944873.

Adding to 20211000 its reverse (11202), we get a palindrome (20222202).

The spelling of 20211000 in words is "twenty million, two hundred eleven thousand".