21002001201 has 12 divisors (see below), whose sum is σ = 31655190528. Its totient is φ = 13392580344.

The previous prime is 21002001199. The next prime is 21002001203. The reversal of 21002001201 is 10210020012.

It is an interprime number because it is at equal distance from previous prime (21002001199) and next prime (21002001203).

It is not a de Polignac number, because 21002001201 - 2¹ = 21002001199 is a prime.

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

It is not an unprimeable number, because it can be changed into a prime (21002001203) 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 11 ways as a sum of consecutive naturals, for example, 50729265 + ... + 50729678.

It is an arithmetic number, because the mean of its divisors is an integer number (2637932544).

Almost surely, 2^21002001201 is an apocalyptic number.

It is an amenable number.

21002001201 is a deficient number, since it is larger than the sum of its proper divisors (10653189327).

21002001201 is a wasteful number, since it uses less digits than its factorization.

21002001201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101458972 (or 101458969 counting only the distinct ones).

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

Adding to 21002001201 its reverse (10210020012), we get a palindrome (31212021213).

The spelling of 21002001201 in words is "twenty-one billion, two million, one thousand, two hundred one".