21230355 has 8 divisors (see below), whose sum is σ = 33968592. Its totient is φ = 11322848.

The previous prime is 21230329. The next prime is 21230359. The reversal of 21230355 is 55303212.

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

It is a cyclic number.

It is not a de Polignac number, because 21230355 - 2⁷ = 21230227 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21230359) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 707664 + ... + 707693.

It is an arithmetic number, because the mean of its divisors is an integer number (4246074).

Almost surely, 2^21230355 is an apocalyptic number.

21230355 is a deficient number, since it is larger than the sum of its proper divisors (12738237).

21230355 is a wasteful number, since it uses less digits than its factorization.

21230355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1415365.

The product of its (nonzero) digits is 900, while the sum is 21.

The square root of 21230355 is about 4607.6409365314. The cubic root of 21230355 is about 276.8975323363.

Adding to 21230355 its reverse (55303212), we get a palindrome (76533567).

The spelling of 21230355 in words is "twenty-one million, two hundred thirty thousand, three hundred fifty-five".