20100201021 has 6 divisors (see below), whose sum is σ = 29033623710. Its totient is φ = 13400134008.

The previous prime is 20100201001. The next prime is 20100201029. The reversal of 20100201021 is 12010200102.

It can be written as a sum of positive squares in only one way, i.e., 18314208900 + 1785992121 = 135330^2 + 42261^2 .

It is not a de Polignac number, because 20100201021 - 2⁶ = 20100200957 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: 2233355669 = 20100201021 / (2 + 0 + 1 + 0 + 0 + 2 + 0 + 1 + 0 + 2 + 1).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20100200994 and 20100201012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20100201029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1116677826 + ... + 1116677843.

It is an arithmetic number, because the mean of its divisors is an integer number (4838937285).

Almost surely, 2^20100201021 is an apocalyptic number.

It is an amenable number.

20100201021 is a deficient number, since it is larger than the sum of its proper divisors (8933422689).

20100201021 is a wasteful number, since it uses less digits than its factorization.

20100201021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2233355675 (or 2233355672 counting only the distinct ones).

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

Adding to 20100201021 its reverse (12010200102), we get a palindrome (32110401123).

The spelling of 20100201021 in words is "twenty billion, one hundred million, two hundred one thousand, twenty-one".