1680750917 has 4 divisors (see below), whose sum is σ = 1779618636. Its totient is φ = 1581883200.

The previous prime is 1680750889. The next prime is 1680750919. The reversal of 1680750917 is 7190570861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7190570861 = 37 ⋅194339753.

It can be written as a sum of positive squares in 2 ways, for example, as 1530296161 + 150454756 = 39119^2 + 12266^2 .

It is a cyclic number.

It is not a de Polignac number, because 1680750917 - 2⁶ = 1680750853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1680750919) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49433834 + ... + 49433867.

It is an arithmetic number, because the mean of its divisors is an integer number (444904659).

Almost surely, 2^1680750917 is an apocalyptic number.

1680750917 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

1680750917 is a deficient number, since it is larger than the sum of its proper divisors (98867719).

1680750917 is an equidigital number, since it uses as much as digits as its factorization.

1680750917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98867718.

The product of its (nonzero) digits is 105840, while the sum is 44.

The square root of 1680750917 is about 40996.9622899063. The cubic root of 1680750917 is about 1188.9614829018.

The spelling of 1680750917 in words is "one billion, six hundred eighty million, seven hundred fifty thousand, nine hundred seventeen".