21384156 has 24 divisors (see below), whose sum is σ = 50029840. Its totient is φ = 7108992.

The previous prime is 21384151. The next prime is 21384161. The reversal of 21384156 is 65148312.

It is an interprime number because it is at equal distance from previous prime (21384151) and next prime (21384161).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21384151) 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 7 ways as a sum of consecutive naturals, for example, 2730 + ... + 7086.

Almost surely, 2^21384156 is an apocalyptic number.

It is an amenable number.

21384156 is an abundant number, since it is smaller than the sum of its proper divisors (28645684).

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

21384156 is a wasteful number, since it uses less digits than its factorization.

21384156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4773 (or 4771 counting only the distinct ones).

The product of its digits is 5760, while the sum is 30.

The square root of 21384156 is about 4624.3005957658. The cubic root of 21384156 is about 277.5645755083.

The spelling of 21384156 in words is "twenty-one million, three hundred eighty-four thousand, one hundred fifty-six".