21105146 has 8 divisors (see below), whose sum is σ = 32176884. Its totient is φ = 10379520.

The previous prime is 21105121. The next prime is 21105169. The reversal of 21105146 is 64150112.

It can be written as a sum of positive squares in 2 ways, for example, as 21058921 + 46225 = 4589^2 + 215^2 .

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

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 in 3 ways as a sum of consecutive naturals, for example, 86375 + ... + 86618.

Almost surely, 2^21105146 is an apocalyptic number.

21105146 is a deficient number, since it is larger than the sum of its proper divisors (11071738).

21105146 is a wasteful number, since it uses less digits than its factorization.

21105146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173056.

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 21105146 is about 4594.0337395365. The cubic root of 21105146 is about 276.3521113339.

Adding to 21105146 its reverse (64150112), we get a palindrome (85255258).

The spelling of 21105146 in words is "twenty-one million, one hundred five thousand, one hundred forty-six".