21604682 has 16 divisors (see below), whose sum is σ = 36891072. Its totient is φ = 9393120.

The previous prime is 21604669. The next prime is 21604699. The reversal of 21604682 is 28640612.

It is a super-2 number, since 2×21604682² = 933524568642248, which contains 22 as substring.

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, 20843 + ... + 21854.

It is an arithmetic number, because the mean of its divisors is an integer number (2305692).

Almost surely, 2^21604682 is an apocalyptic number.

21604682 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21604682 is a deficient number, since it is larger than the sum of its proper divisors (15286390).

21604682 is a wasteful number, since it uses less digits than its factorization.

21604682 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42733.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 21604682 is about 4648.0836911570. The cubic root of 21604682 is about 278.5154507102.

The spelling of 21604682 in words is "twenty-one million, six hundred four thousand, six hundred eighty-two".