21432903 has 8 divisors (see below), whose sum is σ = 30258288. Its totient is φ = 13448064.

The previous prime is 21432881. The next prime is 21432913. The reversal of 21432903 is 30923412.

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

It is not a de Polignac number, because 21432903 - 2¹² = 21428807 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21432913) 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, 210076 + ... + 210177.

It is an arithmetic number, because the mean of its divisors is an integer number (3782286).

Almost surely, 2^21432903 is an apocalyptic number.

21432903 is a deficient number, since it is larger than the sum of its proper divisors (8825385).

21432903 is a wasteful number, since it uses less digits than its factorization.

21432903 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 420273.

The product of its (nonzero) digits is 1296, while the sum is 24.

The square root of 21432903 is about 4629.5683384091. The cubic root of 21432903 is about 277.7753261235.

The spelling of 21432903 in words is "twenty-one million, four hundred thirty-two thousand, nine hundred three".