21434403 has 16 divisors (see below), whose sum is σ = 29293056. Its totient is φ = 13937280.

The previous prime is 21434401. The next prime is 21434417. The reversal of 21434403 is 30443412.

It is not a de Polignac number, because 21434403 - 2¹ = 21434401 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21434403.

It is not an unprimeable number, because it can be changed into a prime (21434401) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21451 + ... + 22427.

It is an arithmetic number, because the mean of its divisors is an integer number (1830816).

Almost surely, 2^21434403 is an apocalyptic number.

21434403 is a deficient number, since it is larger than the sum of its proper divisors (7858653).

21434403 is a wasteful number, since it uses less digits than its factorization.

21434403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1154.

The product of its (nonzero) digits is 1152, while the sum is 21.

The square root of 21434403 is about 4629.7303377195. The cubic root of 21434403 is about 277.7818060868.

Adding to 21434403 its reverse (30443412), we get a palindrome (51877815).

Subtracting 21434403 from its reverse (30443412), we obtain a palindrome (9009009).

The spelling of 21434403 in words is "twenty-one million, four hundred thirty-four thousand, four hundred three".