21210111105 has 8 divisors (see below), whose sum is σ = 33936177792. Its totient is φ = 11312059248.

The previous prime is 21210111077. The next prime is 21210111119. The reversal of 21210111105 is 50111101212.

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

It is not a de Polignac number, because 21210111105 - 2⁸ = 21210110849 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15), and also a Moran number because the ratio is a prime number: 1414007407 = 21210111105 / (2 + 1 + 2 + 1 + 0 + 1 + 1 + 1 + 1 + 0 + 5).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 707003689 + ... + 707003718.

It is an arithmetic number, because the mean of its divisors is an integer number (4242022224).

Almost surely, 2^21210111105 is an apocalyptic number.

It is an amenable number.

21210111105 is a deficient number, since it is larger than the sum of its proper divisors (12726066687).

21210111105 is a wasteful number, since it uses less digits than its factorization.

21210111105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1414007415.

The product of its (nonzero) digits is 20, while the sum is 15.

Adding to 21210111105 its reverse (50111101212), we get a palindrome (71321212317).

The spelling of 21210111105 in words is "twenty-one billion, two hundred ten million, one hundred eleven thousand, one hundred five".