21002001203 has 2 divisors, whose sum is σ = 21002001204. Its totient is φ = 21002001202.

The previous prime is 21002001199. The next prime is 21002001217. The reversal of 21002001203 is 30210020012.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21002001203 - 2² = 21002001199 is a prime.

It is not a weakly prime, because it can be changed into another prime (21002001233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501000601 + 10501000602.

It is an arithmetic number, because the mean of its divisors is an integer number (10501000602).

Almost surely, 2^21002001203 is an apocalyptic number.

21002001203 is a deficient number, since it is larger than the sum of its proper divisors (1).

21002001203 is an equidigital number, since it uses as much as digits as its factorization.

21002001203 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 11.

Adding to 21002001203 its reverse (30210020012), we get a palindrome (51212021215).

The spelling of 21002001203 in words is "twenty-one billion, two million, one thousand, two hundred three".