1591986971 has 2 divisors, whose sum is σ = 1591986972. Its totient is φ = 1591986970.

The previous prime is 1591986937. The next prime is 1591986973. The reversal of 1591986971 is 1796891951.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1591986971 - 2¹⁴ = 1591970587 is a prime.

Together with 1591986973, 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 (1591986973) 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, 795993485 + 795993486.

It is an arithmetic number, because the mean of its divisors is an integer number (795993486).

Almost surely, 2^1591986971 is an apocalyptic number.

1591986971 is a deficient number, since it is larger than the sum of its proper divisors (1).

1591986971 is an equidigital number, since it uses as much as digits as its factorization.

1591986971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1224720, while the sum is 56.

The square root of 1591986971 is about 39899.7114149965. The cubic root of 1591986971 is about 1167.6513067751.

The spelling of 1591986971 in words is "one billion, five hundred ninety-one million, nine hundred eighty-six thousand, nine hundred seventy-one".