1678340405 has 12 divisors (see below), whose sum is σ = 2342826540. Its totient is φ = 1150861824.

The previous prime is 1678340399. The next prime is 1678340407. The reversal of 1678340405 is 5040438761.

It can be written as a sum of positive squares in 2 ways, for example, as 901380529 + 776959876 = 30023^2 + 27874^2 .

It is not a de Polignac number, because 1678340405 - 2⁸ = 1678340149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1678340407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3424940 + ... + 3425429.

It is an arithmetic number, because the mean of its divisors is an integer number (195235545).

Almost surely, 2^1678340405 is an apocalyptic number.

It is an amenable number.

1678340405 is a deficient number, since it is larger than the sum of its proper divisors (664486135).

1678340405 is an equidigital number, since it uses as much as digits as its factorization.

1678340405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6850388 (or 6850381 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 38.

The square root of 1678340405 is about 40967.5530755743. The cubic root of 1678340405 is about 1188.3928130460.

The spelling of 1678340405 in words is "one billion, six hundred seventy-eight million, three hundred forty thousand, four hundred five".