21820201 has 8 divisors (see below), whose sum is σ = 23535680. Its totient is φ = 20110032.

The previous prime is 21820193. The next prime is 21820207. The reversal of 21820201 is 10202812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21820201 - 2³ = 21820193 is a prime.

It is a super-2 number, since 2×21820201² = 952242343360802, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21820207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13030 + ... + 14608.

It is an arithmetic number, because the mean of its divisors is an integer number (2941960).

Almost surely, 2^21820201 is an apocalyptic number.

It is an amenable number.

21820201 is a deficient number, since it is larger than the sum of its proper divisors (1715479).

21820201 is a wasteful number, since it uses less digits than its factorization.

21820201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2655.

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 21820201 is about 4671.2098004693. The cubic root of 21820201 is about 279.4385048662.

The spelling of 21820201 in words is "twenty-one million, eight hundred twenty thousand, two hundred one".