21000212111001 has 16 divisors (see below), whose sum is σ = 28404946059840. Its totient is φ = 13798611099840.

The previous prime is 21000212110987. The next prime is 21000212111029. The reversal of 21000212111001 is 10011121200012.

It is a de Polignac number, because none of the positive numbers 2^k-21000212111001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21000212111101) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100059306 + ... + 100268963.

It is an arithmetic number, because the mean of its divisors is an integer number (1775309128740).

Almost surely, 2^{21000212111001} is an apocalyptic number.

It is an amenable number.

21000212111001 is a deficient number, since it is larger than the sum of its proper divisors (7404733948839).

21000212111001 is a wasteful number, since it uses less digits than its factorization.

21000212111001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200328776.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21000212111001 its reverse (10011121200012), we get a palindrome (31011333311013).

The spelling of 21000212111001 in words is "twenty-one trillion, two hundred twelve million, one hundred eleven thousand, one".