21500016101 has 2 divisors, whose sum is σ = 21500016102. Its totient is φ = 21500016100.

The previous prime is 21500016089. The next prime is 21500016157. The reversal of 21500016101 is 10161000512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13548727201 + 7951288900 = 116399^2 + 89170^2 .

It is a cyclic number.

It is not a de Polignac number, because 21500016101 - 2¹⁰ = 21500015077 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21500016101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21500016701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10750008050 + 10750008051.

It is an arithmetic number, because the mean of its divisors is an integer number (10750008051).

Almost surely, 2^21500016101 is an apocalyptic number.

It is an amenable number.

21500016101 is a deficient number, since it is larger than the sum of its proper divisors (1).

21500016101 is an equidigital number, since it uses as much as digits as its factorization.

21500016101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60, while the sum is 17.

Adding to 21500016101 its reverse (10161000512), we get a palindrome (31661016613).

The spelling of 21500016101 in words is "twenty-one billion, five hundred million, sixteen thousand, one hundred one".