21433516 has 24 divisors (see below), whose sum is σ = 42152544. Its totient is φ = 9461760.

The previous prime is 21433507. The next prime is 21433519. The reversal of 21433516 is 61533412.

It is not an unprimeable number, because it can be changed into a prime (21433519) 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, 7765 + ... + 10156.

It is an arithmetic number, because the mean of its divisors is an integer number (1756356).

Almost surely, 2^21433516 is an apocalyptic number.

21433516 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21433516 is a deficient number, since it is larger than the sum of its proper divisors (20719028).

21433516 is a wasteful number, since it uses less digits than its factorization.

21433516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17961 (or 17959 counting only the distinct ones).

The product of its digits is 2160, while the sum is 25.

The square root of 21433516 is about 4629.6345428122. The cubic root of 21433516 is about 277.7779743050. Note that the first 3 decimals are identical.

Adding to 21433516 its reverse (61533412), we get a palindrome (82966928).

The spelling of 21433516 in words is "twenty-one million, four hundred thirty-three thousand, five hundred sixteen".