21301355 has 4 divisors (see below), whose sum is σ = 25561632. Its totient is φ = 17041080.

The previous prime is 21301339. The next prime is 21301361. The reversal of 21301355 is 55310312.

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

It is not a de Polignac number, because 21301355 - 2⁴ = 21301339 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2130131 + ... + 2130140.

It is an arithmetic number, because the mean of its divisors is an integer number (6390408).

Almost surely, 2^21301355 is an apocalyptic number.

21301355 is a deficient number, since it is larger than the sum of its proper divisors (4260277).

21301355 is an equidigital number, since it uses as much as digits as its factorization.

21301355 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4260276.

The product of its (nonzero) digits is 450, while the sum is 20.

The square root of 21301355 is about 4615.3390991345. The cubic root of 21301355 is about 277.2058620781.

Adding to 21301355 its reverse (55310312), we get a palindrome (76611667).

The spelling of 21301355 in words is "twenty-one million, three hundred one thousand, three hundred fifty-five".