21450012101 has 6 divisors (see below), whose sum is σ = 24952054950. Its totient is φ = 18385724616.

The previous prime is 21450012079. The next prime is 21450012127. The reversal of 21450012101 is 10121005412.

It can be written as a sum of positive squares in only one way, i.e., 14975395876 + 6474616225 = 122374^2 + 80465^2 .

It is not a de Polignac number, because 21450012101 - 2¹⁸ = 21449749957 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21450012101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21450012601) 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 5 ways as a sum of consecutive naturals, for example, 218877626 + ... + 218877723.

It is an arithmetic number, because the mean of its divisors is an integer number (4158675825).

Almost surely, 2^21450012101 is an apocalyptic number.

It is an amenable number.

21450012101 is a deficient number, since it is larger than the sum of its proper divisors (3502042849).

21450012101 is an equidigital number, since it uses as much as digits as its factorization.

21450012101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437755363 (or 437755356 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 17.

Adding to 21450012101 its reverse (10121005412), we get a palindrome (31571017513).

The spelling of 21450012101 in words is "twenty-one billion, four hundred fifty million, twelve thousand, one hundred one".