21100220001 has 12 divisors (see below), whose sum is σ = 34832109312. Its totient is φ = 12057268536.

The previous prime is 21100219963. The next prime is 21100220003. The reversal of 21100220001 is 10002200112.

It is not a de Polignac number, because 21100220001 - 2⁶ = 21100219937 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 (21100220003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 167462001 + ... + 167462126.

It is an arithmetic number, because the mean of its divisors is an integer number (2902675776).

Almost surely, 2^21100220001 is an apocalyptic number.

21100220001 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21100220001 is a deficient number, since it is larger than the sum of its proper divisors (13731889311).

21100220001 is a wasteful number, since it uses less digits than its factorization.

21100220001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334924140 (or 334924137 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 21100220001 its reverse (10002200112), we get a palindrome (31102420113).

The spelling of 21100220001 in words is "twenty-one billion, one hundred million, two hundred twenty thousand, one".