16821820201 has 4 divisors (see below), whose sum is σ = 17553203712. Its totient is φ = 16090436692.

The previous prime is 16821820199. The next prime is 16821820231. The reversal of 16821820201 is 10202812861.

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 not a de Polignac number, because 16821820201 - 2¹ = 16821820199 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16821820231) 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, 365691721 + ... + 365691766.

It is an arithmetic number, because the mean of its divisors is an integer number (4388300928).

Almost surely, 2^16821820201 is an apocalyptic number.

It is an amenable number.

16821820201 is a deficient number, since it is larger than the sum of its proper divisors (731383511).

16821820201 is an equidigital number, since it uses as much as digits as its factorization.

16821820201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 731383510.

The product of its (nonzero) digits is 3072, while the sum is 31.

The spelling of 16821820201 in words is "sixteen billion, eight hundred twenty-one million, eight hundred twenty thousand, two hundred one".