21020101100001 has 8 divisors (see below), whose sum is σ = 31140890518560. Its totient is φ = 14013400733316.

The previous prime is 21020101099979. The next prime is 21020101100027. The reversal of 21020101100001 is 10000110102012.

It is a happy number.

It is not a de Polignac number, because 21020101100001 - 2¹³ = 21020101091809 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (21020101100041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 389261131455 + ... + 389261131508.

It is an arithmetic number, because the mean of its divisors is an integer number (3892611314820).

Almost surely, 2^{21020101100001} is an apocalyptic number.

It is an amenable number.

21020101100001 is a deficient number, since it is larger than the sum of its proper divisors (10120789418559).

21020101100001 is an equidigital number, since it uses as much as digits as its factorization.

21020101100001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 778522262972 (or 778522262966 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 21020101100001 its reverse (10000110102012), we get a palindrome (31020211202013).

The spelling of 21020101100001 in words is "twenty-one trillion, twenty billion, one hundred one million, one hundred thousand, one".