21350005 has 8 divisors (see below), whose sum is σ = 25673400. Its totient is φ = 17044416.

The previous prime is 21349997. The next prime is 21350009. The reversal of 21350005 is 50005312.

It can be written as a sum of positive squares in 4 ways, for example, as 8797156 + 12552849 = 2966^2 + 3543^2 .

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 21350005 - 2³ = 21349997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21350009) 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, 1650 + ... + 6739.

It is an arithmetic number, because the mean of its divisors is an integer number (3209175).

Almost surely, 2^21350005 is an apocalyptic number.

It is an amenable number.

21350005 is a deficient number, since it is larger than the sum of its proper divisors (4323395).

21350005 is an equidigital number, since it uses as much as digits as its factorization.

21350005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8903.

The product of its (nonzero) digits is 150, while the sum is 16.

The square root of 21350005 is about 4620.6065619137. The cubic root of 21350005 is about 277.4167377288.

Adding to 21350005 its reverse (50005312), we get a palindrome (71355317).

The spelling of 21350005 in words is "twenty-one million, three hundred fifty thousand, five".