687971071 has 2 divisors, whose sum is σ = 687971072. Its totient is φ = 687971070.

The previous prime is 687971069. The next prime is 687971099. The reversal of 687971071 is 170179786.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 687971071 - 2¹ = 687971069 is a prime.

Together with 687971069, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (687971051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343985535 + 343985536.

It is an arithmetic number, because the mean of its divisors is an integer number (343985536).

Almost surely, 2^687971071 is an apocalyptic number.

687971071 is a deficient number, since it is larger than the sum of its proper divisors (1).

687971071 is an equidigital number, since it uses as much as digits as its factorization.

687971071 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 148176, while the sum is 46.

The square root of 687971071 is about 26229.2026375184. The cubic root of 687971071 is about 882.7886189865.

The spelling of 687971071 in words is "six hundred eighty-seven million, nine hundred seventy-one thousand, seventy-one".