201001200021 has 6 divisors (see below), whose sum is σ = 290335066710. Its totient is φ = 134000800008.

The previous prime is 201001200011. The next prime is 201001200031. The reversal of 201001200021 is 120002100102.

It is an interprime number because it is at equal distance from previous prime (201001200011) and next prime (201001200031).

It can be written as a sum of positive squares in only one way, i.e., 125464724100 + 75536475921 = 354210^2 + 274839^2 .

It is not a de Polignac number, because 201001200021 - 2¹⁷ = 201001068949 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 22333466669 = 201001200021 / (2 + 0 + 1 + 0 + 0 + 1 + 2 + 0 + 0 + 0 + 2 + 1).

It is a junction number, because it is equal to n+sod(n) for n = 201001199976 and 201001200012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201001200011) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11166733326 + ... + 11166733343.

It is an arithmetic number, because the mean of its divisors is an integer number (48389177785).

Almost surely, 2^201001200021 is an apocalyptic number.

It is an amenable number.

201001200021 is a deficient number, since it is larger than the sum of its proper divisors (89333866689).

201001200021 is a wasteful number, since it uses less digits than its factorization.

201001200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22333466675 (or 22333466672 counting only the distinct ones).

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

Adding to 201001200021 its reverse (120002100102), we get a palindrome (321003300123).

The spelling of 201001200021 in words is "two hundred one billion, one million, two hundred thousand, twenty-one".