21075103 has 4 divisors (see below), whose sum is σ = 24085840. Its totient is φ = 18064368.

The previous prime is 21075091. The next prime is 21075113. The reversal of 21075103 is 30157012.

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

It is a de Polignac number, because none of the positive numbers 2^k-21075103 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 (21075113) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1505358 + ... + 1505371.

It is an arithmetic number, because the mean of its divisors is an integer number (6021460).

Almost surely, 2^21075103 is an apocalyptic number.

21075103 is a deficient number, since it is larger than the sum of its proper divisors (3010737).

21075103 is an equidigital number, since it uses as much as digits as its factorization.

21075103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3010736.

The product of its (nonzero) digits is 210, while the sum is 19.

The square root of 21075103 is about 4590.7627906482. The cubic root of 21075103 is about 276.2209207531.

The spelling of 21075103 in words is "twenty-one million, seventy-five thousand, one hundred three".