1680408251 has 2 divisors, whose sum is σ = 1680408252. Its totient is φ = 1680408250.

The previous prime is 1680408217. The next prime is 1680408253. The reversal of 1680408251 is 1528040861.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1680408251 - 2⁶ = 1680408187 is a prime.

Together with 1680408253, 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 (1680408253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840204125 + 840204126.

It is an arithmetic number, because the mean of its divisors is an integer number (840204126).

Almost surely, 2^1680408251 is an apocalyptic number.

1680408251 is a deficient number, since it is larger than the sum of its proper divisors (1).

1680408251 is an equidigital number, since it uses as much as digits as its factorization.

1680408251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15360, while the sum is 35.

The square root of 1680408251 is about 40992.7829135813. The cubic root of 1680408251 is about 1188.8806768838.

The spelling of 1680408251 in words is "one billion, six hundred eighty million, four hundred eight thousand, two hundred fifty-one".