21290082 has 32 divisors (see below), whose sum is σ = 46759680. Its totient is φ = 6408720.

The previous prime is 21290039. The next prime is 21290083. The reversal of 21290082 is 28009212.

It is not an unprimeable number, because it can be changed into a prime (21290083) 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 15 ways as a sum of consecutive naturals, for example, 9769 + ... + 11747.

It is an arithmetic number, because the mean of its divisors is an integer number (1461240).

Almost surely, 2^21290082 is an apocalyptic number.

21290082 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21290082 is an abundant number, since it is smaller than the sum of its proper divisors (25469598).

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

21290082 is a wasteful number, since it uses less digits than its factorization.

21290082 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2158.

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 21290082 is about 4614.1176838048. The cubic root of 21290082 is about 277.1569529343.

Adding to 21290082 its reverse (28009212), we get a palindrome (49299294).

The spelling of 21290082 in words is "twenty-one million, two hundred ninety thousand, eighty-two".