21001201100101 has 4 divisors (see below), whose sum is σ = 21001640586304. Its totient is φ = 21000761613900.

The previous prime is 21001201100041. The next prime is 21001201100137. The reversal of 21001201100101 is 10100110210012.

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-21001201100101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001201100801) 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, 219671415 + ... + 219766996.

It is an arithmetic number, because the mean of its divisors is an integer number (5250410146576).

Almost surely, 2^{21001201100101} is an apocalyptic number.

It is an amenable number.

21001201100101 is a deficient number, since it is larger than the sum of its proper divisors (439486203).

21001201100101 is an equidigital number, since it uses as much as digits as its factorization.

21001201100101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 439486202.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21001201100101 its reverse (10100110210012), we get a palindrome (31101311310113).

It can be divided in two parts, 21001 and 201100101, that added together give a palindrome (201121102).

The spelling of 21001201100101 in words is "twenty-one trillion, one billion, two hundred one million, one hundred thousand, one hundred one".