21233407 has 4 divisors (see below), whose sum is σ = 22866760. Its totient is φ = 19600056.

The previous prime is 21233389. The next prime is 21233411. The reversal of 21233407 is 70433212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21233407 - 2¹¹ = 21231359 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21233497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 816657 + ... + 816682.

It is an arithmetic number, because the mean of its divisors is an integer number (5716690).

Almost surely, 2^21233407 is an apocalyptic number.

21233407 is a deficient number, since it is larger than the sum of its proper divisors (1633353).

21233407 is a wasteful number, since it uses less digits than its factorization.

21233407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1633352.

The product of its (nonzero) digits is 1008, while the sum is 22.

The square root of 21233407 is about 4607.9721136309. The cubic root of 21233407 is about 276.9108003006.

Adding to 21233407 its reverse (70433212), we get a palindrome (91666619).

The spelling of 21233407 in words is "twenty-one million, two hundred thirty-three thousand, four hundred seven".