21212002201 has 8 divisors (see below), whose sum is σ = 23218182344. Its totient is φ = 19259320320.

The previous prime is 21212002193. The next prime is 21212002261. The reversal of 21212002201 is 10220021212.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 121992025 + 21090010176 = 11045^2 + 145224^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21212002201 - 2³ = 21212002193 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21212002261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13373736 + ... + 13375321.

It is an arithmetic number, because the mean of its divisors is an integer number (2902272793).

Almost surely, 2^21212002201 is an apocalyptic number.

It is an amenable number.

21212002201 is a deficient number, since it is larger than the sum of its proper divisors (2006180143).

21212002201 is a wasteful number, since it uses less digits than its factorization.

21212002201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26749131.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21212002201 its reverse (10220021212), we get a palindrome (31432023413).

The spelling of 21212002201 in words is "twenty-one billion, two hundred twelve million, two thousand, two hundred one".