391656036971 has 2 divisors, whose sum is σ = 391656036972. Its totient is φ = 391656036970.

The previous prime is 391656036931. The next prime is 391656036973. The reversal of 391656036971 is 179630656193.

It is a strong prime.

It is an emirp because it is prime and its reverse (179630656193) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-391656036971 is a prime.

Together with 391656036973, 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 (391656036973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195828018485 + 195828018486.

It is an arithmetic number, because the mean of its divisors is an integer number (195828018486).

Almost surely, 2^391656036971 is an apocalyptic number.

391656036971 is a deficient number, since it is larger than the sum of its proper divisors (1).

391656036971 is an equidigital number, since it uses as much as digits as its factorization.

391656036971 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5511240, while the sum is 56.

The spelling of 391656036971 in words is "three hundred ninety-one billion, six hundred fifty-six million, thirty-six thousand, nine hundred seventy-one".