21101020001 has 16 divisors (see below), whose sum is σ = 21547868160. Its totient is φ = 20659354560.

The previous prime is 21101019959. The next prime is 21101020051. The reversal of 21101020001 is 10002010112.

It is a cyclic number.

It is not a de Polignac number, because 21101020001 - 2²² = 21096825697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21101020051) 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, 5474591 + ... + 5478443.

It is an arithmetic number, because the mean of its divisors is an integer number (1346741760).

Almost surely, 2^21101020001 is an apocalyptic number.

It is an amenable number.

21101020001 is a deficient number, since it is larger than the sum of its proper divisors (446848159).

21101020001 is a wasteful number, since it uses less digits than its factorization.

21101020001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4496.

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 21101020001 its reverse (10002010112), we get a palindrome (31103030113).

The spelling of 21101020001 in words is "twenty-one billion, one hundred one million, twenty thousand, one".