21345303 has 32 divisors (see below), whose sum is σ = 34839040. Its totient is φ = 11352960.

The previous prime is 21345287. The next prime is 21345347. The reversal of 21345303 is 30354312.

It is not a de Polignac number, because 21345303 - 2⁴ = 21345287 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21345303.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21345383) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23901 + ... + 24777.

It is an arithmetic number, because the mean of its divisors is an integer number (1088720).

Almost surely, 2^21345303 is an apocalyptic number.

21345303 is a deficient number, since it is larger than the sum of its proper divisors (13493737).

21345303 is a wasteful number, since it uses less digits than its factorization.

21345303 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 967.

The product of its (nonzero) digits is 1080, while the sum is 21.

The square root of 21345303 is about 4620.0977262391. The cubic root of 21345303 is about 277.3963706879.

Adding to 21345303 its reverse (30354312), we get a palindrome (51699615).

Subtracting 21345303 from its reverse (30354312), we obtain a palindrome (9009009).

The spelling of 21345303 in words is "twenty-one million, three hundred forty-five thousand, three hundred three".