201200100021 has 12 divisors (see below), whose sum is σ = 292082783200. Its totient is φ = 133459361640.

The previous prime is 201200099957. The next prime is 201200100077. The reversal of 201200100021 is 120001002102.

It is not a de Polignac number, because 201200100021 - 2⁶ = 201200099957 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201200099976 and 201200100012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201200101021) 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, 56167975 + ... + 56171556.

Almost surely, 2^201200100021 is an apocalyptic number.

It is an amenable number.

201200100021 is a deficient number, since it is larger than the sum of its proper divisors (90882683179).

201200100021 is a wasteful number, since it uses less digits than its factorization.

201200100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112339736 (or 112339733 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 201200100021 its reverse (120001002102), we get a palindrome (321201102123).

The spelling of 201200100021 in words is "two hundred one billion, two hundred million, one hundred thousand, twenty-one".