201021000 has 128 divisors (see below), whose sum is σ = 644492160. Its totient is φ = 52128000.

The previous prime is 201020987. The next prime is 201021043. The reversal of 201021000 is 120102.

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 201021000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 110095 + ... + 111905.

It is an arithmetic number, because the mean of its divisors is an integer number (5035095).

Almost surely, 2^201021000 is an apocalyptic number.

201021000 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 201021000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (322246080).

201021000 is an abundant number, since it is smaller than the sum of its proper divisors (443471160).

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

201021000 is a wasteful number, since it uses less digits than its factorization.

201021000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1872 (or 1858 counting only the distinct ones).

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

The square root of 201021000 is about 14178.1874723111. The cubic root of 201021000 is about 585.7969997348.

Adding to 201021000 its reverse (120102), we get a palindrome (201141102).

The spelling of 201021000 in words is "two hundred one million, twenty-one thousand".