21123030101 has 8 divisors (see below), whose sum is σ = 21278002200. Its totient is φ = 20968316928.

The previous prime is 21123030079. The next prime is 21123030119. The reversal of 21123030101 is 10103032112.

It can be written as a sum of positive squares in 4 ways, for example, as 11024790001 + 10098240100 = 104999^2 + 100490^2 .

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 21123030101 - 2¹⁸ = 21122767957 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 (21123030161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 100565 + ... + 228821.

It is an arithmetic number, because the mean of its divisors is an integer number (2659750275).

Almost surely, 2^21123030101 is an apocalyptic number.

It is an amenable number.

21123030101 is a deficient number, since it is larger than the sum of its proper divisors (154972099).

21123030101 is a wasteful number, since it uses less digits than its factorization.

21123030101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129463.

The product of its (nonzero) digits is 36, while the sum is 14.

Adding to 21123030101 its reverse (10103032112), we get a palindrome (31226062213).

The spelling of 21123030101 in words is "twenty-one billion, one hundred twenty-three million, thirty thousand, one hundred one".