21010103 has 8 divisors (see below), whose sum is σ = 21370272. Its totient is φ = 20653056.

The previous prime is 21010097. The next prime is 21010111. The reversal of 21010103 is 30101012.

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 21010103 - 2¹⁴ = 20993719 is a prime.

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

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010153) 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, 15551 + ... + 16847.

It is an arithmetic number, because the mean of its divisors is an integer number (2671284).

Almost surely, 2^21010103 is an apocalyptic number.

21010103 is a deficient number, since it is larger than the sum of its proper divisors (360169).

21010103 is a wasteful number, since it uses less digits than its factorization.

21010103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1561.

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

The square root of 21010103 is about 4583.6778900791. The cubic root of 21010103 is about 275.9366540543.

Adding to 21010103 its reverse (30101012), we get a palindrome (51111115).

Subtracting 21010103 from its reverse (30101012), we obtain a palindrome (9090909).

The spelling of 21010103 in words is "twenty-one million, ten thousand, one hundred three".