21384546 has 16 divisors (see below), whose sum is σ = 43576704. Its totient is φ = 6993584.

The previous prime is 21384533. The next prime is 21384613. The reversal of 21384546 is 64548312.

It is a super-2 number, since 2×21384546² = 914597615252232, which contains 22 as substring.

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 7 ways as a sum of consecutive naturals, for example, 33306 + ... + 33941.

It is an arithmetic number, because the mean of its divisors is an integer number (2723544).

Almost surely, 2^21384546 is an apocalyptic number.

21384546 is an abundant number, since it is smaller than the sum of its proper divisors (22192158).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21384546 is a wasteful number, since it uses less digits than its factorization.

21384546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67305.

The product of its digits is 23040, while the sum is 33.

The square root of 21384546 is about 4624.3427641125. The cubic root of 21384546 is about 277.5662628873.

It can be divided in two parts, 2138454 and 6, that multiplied together give a square (12830724 = 3582²).

The spelling of 21384546 in words is "twenty-one million, three hundred eighty-four thousand, five hundred forty-six".