21201200020001 has 4 divisors (see below), whose sum is σ = 21211348992900. Its totient is φ = 21191051047104.

The previous prime is 21201200019983. The next prime is 21201200020043. The reversal of 21201200020001 is 10002000210212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13973571039376 + 7227628980625 = 3738124^2 + 2688425^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201200020001 - 2³⁸ = 20926322113057 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21201200023001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5074483316 + ... + 5074487493.

It is an arithmetic number, because the mean of its divisors is an integer number (5302837248225).

Almost surely, 2^{21201200020001} is an apocalyptic number.

It is an amenable number.

21201200020001 is a deficient number, since it is larger than the sum of its proper divisors (10148972899).

21201200020001 is a wasteful number, since it uses less digits than its factorization.

21201200020001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10148972898.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21201200020001 its reverse (10002000210212), we get a palindrome (31203200230213).

The spelling of 21201200020001 in words is "twenty-one trillion, two hundred one billion, two hundred million, twenty thousand, one".