21011212273 has 2 divisors, whose sum is σ = 21011212274. Its totient is φ = 21011212272.

The previous prime is 21011212267. The next prime is 21011212297. The reversal of 21011212273 is 37221211012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11822647824 + 9188564449 = 108732^2 + 95857^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21011212273 is a prime.

It is not a weakly prime, because it can be changed into another prime (21011218273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505606136 + 10505606137.

It is an arithmetic number, because the mean of its divisors is an integer number (10505606137).

Almost surely, 2^21011212273 is an apocalyptic number.

It is an amenable number.

21011212273 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011212273 is an equidigital number, since it uses as much as digits as its factorization.

21011212273 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 336, while the sum is 22.

Adding to 21011212273 its reverse (37221211012), we get a palindrome (58232423285).

The spelling of 21011212273 in words is "twenty-one billion, eleven million, two hundred twelve thousand, two hundred seventy-three".