21530876 has 24 divisors (see below), whose sum is σ = 41034000. Its totient is φ = 9846144.

The previous prime is 21530867. The next prime is 21530903. The reversal of 21530876 is 67803512.

It is a happy number.

It is a congruent number.

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, 2681 + ... + 7088.

It is an arithmetic number, because the mean of its divisors is an integer number (1709750).

Almost surely, 2^21530876 is an apocalyptic number.

It is an amenable number.

21530876 is a deficient number, since it is larger than the sum of its proper divisors (19503124).

21530876 is a wasteful number, since it uses less digits than its factorization.

21530876 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9821 (or 9819 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 21530876 is about 4640.1374979627. The cubic root of 21530876 is about 278.1979336733.

The spelling of 21530876 in words is "twenty-one million, five hundred thirty thousand, eight hundred seventy-six".