21018466 has 16 divisors (see below), whose sum is σ = 36095040. Its totient is φ = 8992080.

The previous prime is 21018461. The next prime is 21018467. The reversal of 21018466 is 66481012.

It is not an unprimeable number, because it can be changed into a prime (21018461) 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, 10701 + ... + 12511.

It is an arithmetic number, because the mean of its divisors is an integer number (2255940).

Almost surely, 2^21018466 is an apocalyptic number.

21018466 is a deficient number, since it is larger than the sum of its proper divisors (15076574).

21018466 is a wasteful number, since it uses less digits than its factorization.

21018466 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2649.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 21018466 is about 4584.5900580095. The cubic root of 21018466 is about 275.9732610797.

Adding to 21018466 its reverse (66481012), we get a palindrome (87499478).

The spelling of 21018466 in words is "twenty-one million, eighteen thousand, four hundred sixty-six".