201021100 has 36 divisors (see below), whose sum is σ = 498534064. Its totient is φ = 68921280.

The previous prime is 201021091. The next prime is 201021101. The reversal of 201021100 is 1120102.

It is a Harshad number since it is a multiple of its sum of digits (7).

It is not an unprimeable number, because it can be changed into a prime (201021101) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 142887 + ... + 144286.

Almost surely, 2^201021100 is an apocalyptic number.

201021100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201021100 is an abundant number, since it is smaller than the sum of its proper divisors (297512964).

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

201021100 is a wasteful number, since it uses less digits than its factorization.

201021100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 287194 (or 287187 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 7.

The square root of 201021100 is about 14178.1909988545. The cubic root of 201021100 is about 585.7970968717.

Adding to 201021100 its reverse (1120102), we get a palindrome (202141202).

The spelling of 201021100 in words is "two hundred one million, twenty-one thousand, one hundred".