21420301 has 6 divisors (see below), whose sum is σ = 24917550. Its totient is φ = 18360216.

The previous prime is 21420293. The next prime is 21420331. The reversal of 21420301 is 10302412.

It can be written as a sum of positive squares in only one way, i.e., 18714276 + 2706025 = 4326^2 + 1645^2 .

It is not a de Polignac number, because 21420301 - 2³ = 21420293 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21420331) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 218526 + ... + 218623.

It is an arithmetic number, because the mean of its divisors is an integer number (4152925).

Almost surely, 2^21420301 is an apocalyptic number.

It is an amenable number.

21420301 is a deficient number, since it is larger than the sum of its proper divisors (3497249).

21420301 is an equidigital number, since it uses as much as digits as its factorization.

21420301 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437163 (or 437156 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 21420301 is about 4628.2071042683. The cubic root of 21420301 is about 277.7208738490.

Adding to 21420301 its reverse (10302412), we get a palindrome (31722713).

The spelling of 21420301 in words is "twenty-one million, four hundred twenty thousand, three hundred one".