671287478249 has 2 divisors, whose sum is σ = 671287478250. Its totient is φ = 671287478248.

The previous prime is 671287478221. The next prime is 671287478287. The reversal of 671287478249 is 942874782176.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 403025634649 + 268261843600 = 634843^2 + 517940^2 .

It is a cyclic number.

It is not a de Polignac number, because 671287478249 - 2¹² = 671287474153 is a prime.

It is not a weakly prime, because it can be changed into another prime (671287477249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335643739124 + 335643739125.

It is an arithmetic number, because the mean of its divisors is an integer number (335643739125).

Almost surely, 2^671287478249 is an apocalyptic number.

It is an amenable number.

671287478249 is a deficient number, since it is larger than the sum of its proper divisors (1).

671287478249 is an equidigital number, since it uses as much as digits as its factorization.

671287478249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 75866112, while the sum is 65.

The spelling of 671287478249 in words is "six hundred seventy-one billion, two hundred eighty-seven million, four hundred seventy-eight thousand, two hundred forty-nine".