21353546 has 4 divisors (see below), whose sum is σ = 32030322. Its totient is φ = 10676772.

The previous prime is 21353539. The next prime is 21353561. The reversal of 21353546 is 64535312.

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

It can be written as a sum of positive squares in only one way, i.e., 16313521 + 5040025 = 4039^2 + 2245^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5338385 + ... + 5338388.

Almost surely, 2^21353546 is an apocalyptic number.

21353546 is a deficient number, since it is larger than the sum of its proper divisors (10676776).

21353546 is a wasteful number, since it uses less digits than its factorization.

21353546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10676775.

The product of its digits is 10800, while the sum is 29.

The square root of 21353546 is about 4620.9897208282. The cubic root of 21353546 is about 277.4320738433.

Adding to 21353546 its reverse (64535312), we get a palindrome (85888858).

The spelling of 21353546 in words is "twenty-one million, three hundred fifty-three thousand, five hundred forty-six".