21002002210001 has 4 divisors (see below), whose sum is σ = 21141088317504. Its totient is φ = 20862916102500.

The previous prime is 21002002209989. The next prime is 21002002210009. The reversal of 21002002210001 is 10001220020012.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21002002210001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21002002210009) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69543053525 + ... + 69543053826.

It is an arithmetic number, because the mean of its divisors is an integer number (5285272079376).

Almost surely, 2^{21002002210001} is an apocalyptic number.

It is an amenable number.

21002002210001 is a deficient number, since it is larger than the sum of its proper divisors (139086107503).

21002002210001 is a wasteful number, since it uses less digits than its factorization.

21002002210001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139086107502.

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

Adding to 21002002210001 its reverse (10001220020012), we get a palindrome (31003222230013).

The spelling of 21002002210001 in words is "twenty-one trillion, two billion, two million, two hundred ten thousand, one".