21001230001 has 2 divisors, whose sum is σ = 21001230002. Its totient is φ = 21001230000.

The previous prime is 21001229993. The next prime is 21001230049. The reversal of 21001230001 is 10003210012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16831170225 + 4170059776 = 129735^2 + 64576^2 .

It is a cyclic number.

It is not a de Polignac number, because 21001230001 - 2³ = 21001229993 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21001230001.

It is not a weakly prime, because it can be changed into another prime (21001200001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500615000 + 10500615001.

It is an arithmetic number, because the mean of its divisors is an integer number (10500615001).

Almost surely, 2^21001230001 is an apocalyptic number.

It is an amenable number.

21001230001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001230001 is an equidigital number, since it uses as much as digits as its factorization.

21001230001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12, while the sum is 10.

Adding to 21001230001 its reverse (10003210012), we get a palindrome (31004440013).

The spelling of 21001230001 in words is "twenty-one billion, one million, two hundred thirty thousand, one".