21486239321 has 2 divisors, whose sum is σ = 21486239322. Its totient is φ = 21486239320.

The previous prime is 21486239317. The next prime is 21486239323. The reversal of 21486239321 is 12393268412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20012063296 + 1474176025 = 141464^2 + 38395^2 .

It is a cyclic number.

It is not a de Polignac number, because 21486239321 - 2² = 21486239317 is a prime.

Together with 21486239323, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21486239323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10743119660 + 10743119661.

It is an arithmetic number, because the mean of its divisors is an integer number (10743119661).

Almost surely, 2^21486239321 is an apocalyptic number.

It is an amenable number.

21486239321 is a deficient number, since it is larger than the sum of its proper divisors (1).

21486239321 is an equidigital number, since it uses as much as digits as its factorization.

21486239321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 124416, while the sum is 41.

The spelling of 21486239321 in words is "twenty-one billion, four hundred eighty-six million, two hundred thirty-nine thousand, three hundred twenty-one".