21001103 has 8 divisors (see below), whose sum is σ = 22388400. Its totient is φ = 19630720.

The previous prime is 21001087. The next prime is 21001117. The reversal of 21001103 is 30110012.

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

It is a cyclic number.

It is not a de Polignac number, because 21001103 - 2⁴ = 21001087 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 (21001153) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1613 + ... + 6678.

It is an arithmetic number, because the mean of its divisors is an integer number (2798550).

Almost surely, 2^21001103 is an apocalyptic number.

21001103 is a deficient number, since it is larger than the sum of its proper divisors (1387297).

21001103 is a wasteful number, since it uses less digits than its factorization.

21001103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8457.

The product of its (nonzero) digits is 6, while the sum is 8.

The square root of 21001103 is about 4582.6960405421. The cubic root of 21001103 is about 275.8972478605.

Adding to 21001103 its reverse (30110012), we get a palindrome (51111115).

The spelling of 21001103 in words is "twenty-one million, one thousand, one hundred three".