21000273101 has 2 divisors, whose sum is σ = 21000273102. Its totient is φ = 21000273100.

The previous prime is 21000273097. The next prime is 21000273131. The reversal of 21000273101 is 10137200012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11046220201 + 9954052900 = 105101^2 + 99770^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000273101 - 2² = 21000273097 is a prime.

It is a super-2 number, since 2×21000273101² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21000273101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21000273131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500136550 + 10500136551.

It is an arithmetic number, because the mean of its divisors is an integer number (10500136551).

Almost surely, 2^21000273101 is an apocalyptic number.

It is an amenable number.

21000273101 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000273101 is an equidigital number, since it uses as much as digits as its factorization.

21000273101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84, while the sum is 17.

Adding to 21000273101 its reverse (10137200012), we get a palindrome (31137473113).

The spelling of 21000273101 in words is "twenty-one billion, two hundred seventy-three thousand, one hundred one".