21650345 has 16 divisors (see below), whose sum is σ = 26784000. Its totient is φ = 16793088.

The previous prime is 21650339. The next prime is 21650351. The reversal of 21650345 is 54305612.

It is an interprime number because it is at equal distance from previous prime (21650339) and next prime (21650351).

It is a cyclic number.

It is not a de Polignac number, because 21650345 - 2⁶ = 21650281 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 22841 + ... + 23769.

It is an arithmetic number, because the mean of its divisors is an integer number (1674000).

Almost surely, 2^21650345 is an apocalyptic number.

It is an amenable number.

21650345 is a deficient number, since it is larger than the sum of its proper divisors (5133655).

21650345 is an equidigital number, since it uses as much as digits as its factorization.

21650345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1072.

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 21650345 is about 4652.9931227114. The cubic root of 21650345 is about 278.7115332308.

Adding to 21650345 its reverse (54305612), we get a palindrome (75955957).

The spelling of 21650345 in words is "twenty-one million, six hundred fifty thousand, three hundred forty-five".