21011001222001 has 32 divisors (see below), whose sum is σ = 26763818065920. Its totient is φ = 16057596038400.

The previous prime is 21011001221941. The next prime is 21011001222017. The reversal of 21011001222001 is 10022210011012.

It is not a de Polignac number, because 21011001222001 - 2¹³ = 21011001213809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21011001222031) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 162797586 + ... + 162926596.

It is an arithmetic number, because the mean of its divisors is an integer number (836369314560).

Almost surely, 2^{21011001222001} is an apocalyptic number.

It is an amenable number.

21011001222001 is a deficient number, since it is larger than the sum of its proper divisors (5752816843919).

21011001222001 is a wasteful number, since it uses less digits than its factorization.

21011001222001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201085.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21011001222001 its reverse (10022210011012), we get a palindrome (31033211233013).

The spelling of 21011001222001 in words is "twenty-one trillion, eleven billion, one million, two hundred twenty-two thousand, one".