21277347439 has 2 divisors, whose sum is σ = 21277347440. Its totient is φ = 21277347438.

The previous prime is 21277347433. The next prime is 21277347479. The reversal of 21277347439 is 93474377212.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21277347439 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21277347392 and 21277347401.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21277347433) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10638673719 + 10638673720.

It is an arithmetic number, because the mean of its divisors is an integer number (10638673720).

Almost surely, 2^21277347439 is an apocalyptic number.

21277347439 is a deficient number, since it is larger than the sum of its proper divisors (1).

21277347439 is an equidigital number, since it uses as much as digits as its factorization.

21277347439 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1778112, while the sum is 49.

The spelling of 21277347439 in words is "twenty-one billion, two hundred seventy-seven million, three hundred forty-seven thousand, four hundred thirty-nine".