21445346 has 8 divisors (see below), whose sum is σ = 34642524. Its totient is φ = 9897840.

The previous prime is 21445331. The next prime is 21445349. The reversal of 21445346 is 64354412.

It can be written as a sum of positive squares in 2 ways, for example, as 19228225 + 2217121 = 4385^2 + 1489^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21445349) 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 3 ways as a sum of consecutive naturals, for example, 412385 + ... + 412436.

Almost surely, 2^21445346 is an apocalyptic number.

21445346 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21445346 is a deficient number, since it is larger than the sum of its proper divisors (13197178).

21445346 is a wasteful number, since it uses less digits than its factorization.

21445346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 824836.

The product of its digits is 11520, while the sum is 29.

The square root of 21445346 is about 4630.9120052102. The cubic root of 21445346 is about 277.8290704332.

Adding to 21445346 its reverse (64354412), we get a palindrome (85799758).

The spelling of 21445346 in words is "twenty-one million, four hundred forty-five thousand, three hundred forty-six".