21042466 has 8 divisors (see below), whose sum is σ = 31585104. Its totient is φ = 10514100.

The previous prime is 21042457. The next prime is 21042467. The reversal of 21042466 is 66424012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21042466² = 885570750722312, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21042466.

It is not an unprimeable number, because it can be changed into a prime (21042467) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1641 + ... + 6691.

It is an arithmetic number, because the mean of its divisors is an integer number (3948138).

Almost surely, 2^21042466 is an apocalyptic number.

21042466 is a deficient number, since it is larger than the sum of its proper divisors (10542638).

21042466 is a wasteful number, since it uses less digits than its factorization.

21042466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7136.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 21042466 is about 4587.2067753700. The cubic root of 21042466 is about 276.0782614303.

Adding to 21042466 its reverse (66424012), we get a palindrome (87466478).

The spelling of 21042466 in words is "twenty-one million, forty-two thousand, four hundred sixty-six".