21213201 has 8 divisors (see below), whose sum is σ = 28427200. Its totient is φ = 14070672.

The previous prime is 21213193. The next prime is 21213251. The reversal of 21213201 is 10231212.

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

It is not a de Polignac number, because 21213201 - 2³ = 21213193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21213251) 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, 17170 + ... + 18363.

It is an arithmetic number, because the mean of its divisors is an integer number (3553400).

Almost surely, 2^21213201 is an apocalyptic number.

It is an amenable number.

21213201 is a deficient number, since it is larger than the sum of its proper divisors (7213999).

21213201 is a wasteful number, since it uses less digits than its factorization.

21213201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35735.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 21213201 is about 4605.7790871904. The cubic root of 21213201 is about 276.8229350573.

Adding to 21213201 its reverse (10231212), we get a palindrome (31444413).

The spelling of 21213201 in words is "twenty-one million, two hundred thirteen thousand, two hundred one".