21384030 has 32 divisors (see below), whose sum is σ = 51904800. Its totient is φ = 5637632.

The previous prime is 21383969. The next prime is 21384061. The reversal of 21384030 is 3048312.

21384030 = 45² + 46² + ... + 400².

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21383988 and 21384006.

It is a congruent number.

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, 1335 + ... + 6674.

It is an arithmetic number, because the mean of its divisors is an integer number (1622025).

Almost surely, 2^21384030 is an apocalyptic number.

21384030 is an abundant number, since it is smaller than the sum of its proper divisors (30520770).

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

21384030 is a wasteful number, since it uses less digits than its factorization.

21384030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8108.

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 21384030 is about 4624.2869720639. The cubic root of 21384030 is about 277.5640303507.

The spelling of 21384030 in words is "twenty-one million, three hundred eighty-four thousand, thirty".