6921740239 has 2 divisors, whose sum is σ = 6921740240. Its totient is φ = 6921740238.

The previous prime is 6921740237. The next prime is 6921740297. The reversal of 6921740239 is 9320471296.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6921740239 - 2¹ = 6921740237 is a prime.

Together with 6921740237, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 6921740195 and 6921740204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6921740237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3460870119 + 3460870120.

It is an arithmetic number, because the mean of its divisors is an integer number (3460870120).

Almost surely, 2^6921740239 is an apocalyptic number.

6921740239 is a deficient number, since it is larger than the sum of its proper divisors (1).

6921740239 is an equidigital number, since it uses as much as digits as its factorization.

6921740239 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 163296, while the sum is 43.

The square root of 6921740239 is about 83196.9965743956. The cubic root of 6921740239 is about 1905.7756147096.

The spelling of 6921740239 in words is "six billion, nine hundred twenty-one million, seven hundred forty thousand, two hundred thirty-nine".