21233040 has 40 divisors (see below), whose sum is σ = 65823168. Its totient is φ = 5662080.

The previous prime is 21233029. The next prime is 21233059. The reversal of 21233040 is 4033212.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43996 + ... + 44475.

Almost surely, 2^21233040 is an apocalyptic number.

21233040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21233040 is an abundant number, since it is smaller than the sum of its proper divisors (44590128).

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

21233040 is a wasteful number, since it uses less digits than its factorization.

21233040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88487 (or 88481 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 21233040 is about 4607.9322911692. The cubic root of 21233040 is about 276.9092049082.

Adding to 21233040 its reverse (4033212), we get a palindrome (25266252).

The spelling of 21233040 in words is "twenty-one million, two hundred thirty-three thousand, forty".