21254201 has 4 divisors (see below), whose sum is σ = 21279972. Its totient is φ = 21228432.

The previous prime is 21254183. The next prime is 21254213. The reversal of 21254201 is 10245212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6996025 + 14258176 = 2645^2 + 3776^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21254201 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21254201.

It is not an unprimeable number, because it can be changed into a prime (21254221) 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, 11606 + ... + 13311.

It is an arithmetic number, because the mean of its divisors is an integer number (5319993).

Almost surely, 2^21254201 is an apocalyptic number.

It is an amenable number.

21254201 is a deficient number, since it is larger than the sum of its proper divisors (25771).

21254201 is an equidigital number, since it uses as much as digits as its factorization.

21254201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25770.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 21254201 is about 4610.2278685549. The cubic root of 21254201 is about 277.0011642659.

Adding to 21254201 its reverse (10245212), we get a palindrome (31499413).

The spelling of 21254201 in words is "twenty-one million, two hundred fifty-four thousand, two hundred one".