21042876 has 24 divisors (see below), whose sum is σ = 49233744. Its totient is φ = 6995200.

The previous prime is 21042863. The next prime is 21042877. The reversal of 21042876 is 67824012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21042877) by changing a digit.

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, 2626 + ... + 6998.

It is an arithmetic number, because the mean of its divisors is an integer number (2051406).

Almost surely, 2^21042876 is an apocalyptic number.

It is an amenable number.

21042876 is an abundant number, since it is smaller than the sum of its proper divisors (28190868).

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

21042876 is a wasteful number, since it uses less digits than its factorization.

21042876 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4781 (or 4779 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 21042876 is about 4587.2514646572. The cubic root of 21042876 is about 276.0800544925.

Adding to 21042876 its reverse (67824012), we get a palindrome (88866888).

The spelling of 21042876 in words is "twenty-one million, forty-two thousand, eight hundred seventy-six".