21111010103 has 4 divisors (see below), whose sum is σ = 21111775440. Its totient is φ = 21110244768.

The previous prime is 21111010031. The next prime is 21111010127. The reversal of 21111010103 is 30101011112.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21111010103 - 2³⁴ = 3931140919 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 (21111010603) 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, 339683 + ... + 396996.

It is an arithmetic number, because the mean of its divisors is an integer number (5277943860).

Almost surely, 2^21111010103 is an apocalyptic number.

21111010103 is a deficient number, since it is larger than the sum of its proper divisors (765337).

21111010103 is an equidigital number, since it uses as much as digits as its factorization.

21111010103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 765336.

The product of its (nonzero) digits is 6, while the sum is 11.

Adding to 21111010103 its reverse (30101011112), we get a palindrome (51212021215).

The spelling of 21111010103 in words is "twenty-one billion, one hundred eleven million, ten thousand, one hundred three".