21012002201 has 8 divisors (see below), whose sum is σ = 21180933000. Its totient is φ = 20843443840.

The previous prime is 21012002197. The next prime is 21012002243. The reversal of 21012002201 is 10220021012.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 50176 + 21011952025 = 224^2 + 144955^2 .

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 21012002201 - 2² = 21012002197 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21012002251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20735 + ... + 206043.

It is an arithmetic number, because the mean of its divisors is an integer number (2647616625).

Almost surely, 2^21012002201 is an apocalyptic number.

It is an amenable number.

21012002201 is a deficient number, since it is larger than the sum of its proper divisors (168930799).

21012002201 is a wasteful number, since it uses less digits than its factorization.

21012002201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186219.

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

Adding to 21012002201 its reverse (10220021012), we get a palindrome (31232023213).

The spelling of 21012002201 in words is "twenty-one billion, twelve million, two thousand, two hundred one".