21382847 has 16 divisors (see below), whose sum is σ = 23708160. Its totient is φ = 19194912.

The previous prime is 21382843. The next prime is 21382859. The reversal of 21382847 is 74828312.

It is a cyclic number.

It is not a de Polignac number, because 21382847 - 2² = 21382843 is a prime.

It is a super-2 number, since 2×21382847² = 914452291650818, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21382843) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72833 + ... + 73125.

It is an arithmetic number, because the mean of its divisors is an integer number (1481760).

Almost surely, 2^21382847 is an apocalyptic number.

21382847 is a deficient number, since it is larger than the sum of its proper divisors (2325313).

21382847 is a wasteful number, since it uses less digits than its factorization.

21382847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 502.

The product of its digits is 21504, while the sum is 35.

The square root of 21382847 is about 4624.1590586830. The cubic root of 21382847 is about 277.5589118222.

The spelling of 21382847 in words is "twenty-one million, three hundred eighty-two thousand, eight hundred forty-seven".