21012012210103 has 4 divisors (see below), whose sum is σ = 21017508424288. Its totient is φ = 21006515995920.

The previous prime is 21012012210083. The next prime is 21012012210149. The reversal of 21012012210103 is 30101221021012.

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 21012012210103 - 2²⁹ = 21011475339191 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 (21012012210503) 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, 2748101358 + ... + 2748109003.

It is an arithmetic number, because the mean of its divisors is an integer number (5254377106072).

Almost surely, 2^{21012012210103} is an apocalyptic number.

21012012210103 is a deficient number, since it is larger than the sum of its proper divisors (5496214185).

21012012210103 is an equidigital number, since it uses as much as digits as its factorization.

21012012210103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5496214184.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21012012210103 its reverse (30101221021012), we get a palindrome (51113233231115).

The spelling of 21012012210103 in words is "twenty-one trillion, twelve billion, twelve million, two hundred ten thousand, one hundred three".