21212312273 has 2 divisors, whose sum is σ = 21212312274. Its totient is φ = 21212312272.

The previous prime is 21212312171. The next prime is 21212312279. The reversal of 21212312273 is 37221321212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21208970689 + 3341584 = 145633^2 + 1828^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212312273 - 2²² = 21208117969 is a prime.

It is not a weakly prime, because it can be changed into another prime (21212312279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606156136 + 10606156137.

It is an arithmetic number, because the mean of its divisors is an integer number (10606156137).

Almost surely, 2^21212312273 is an apocalyptic number.

It is an amenable number.

21212312273 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212312273 is an equidigital number, since it uses as much as digits as its factorization.

21212312273 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2016, while the sum is 26.

Adding to 21212312273 its reverse (37221321212), we get a palindrome (58433633485).

The spelling of 21212312273 in words is "twenty-one billion, two hundred twelve million, three hundred twelve thousand, two hundred seventy-three".