21300655 has 4 divisors (see below), whose sum is σ = 25560792. Its totient is φ = 17040520.

The previous prime is 21300649. The next prime is 21300659. The reversal of 21300655 is 55600312.

It is a happy number.

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

It is not a de Polignac number, because 21300655 - 2⁷ = 21300527 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21300659) 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, 2130061 + ... + 2130070.

It is an arithmetic number, because the mean of its divisors is an integer number (6390198).

Almost surely, 2^21300655 is an apocalyptic number.

21300655 is a deficient number, since it is larger than the sum of its proper divisors (4260137).

21300655 is an equidigital number, since it uses as much as digits as its factorization.

21300655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4260136.

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 21300655 is about 4615.2632644303. The cubic root of 21300655 is about 277.2028255540.

Adding to 21300655 its reverse (55600312), we get a palindrome (76900967).

The spelling of 21300655 in words is "twenty-one million, three hundred thousand, six hundred fifty-five".