680396649 has 32 divisors (see below), whose sum is σ = 981147648. Its totient is φ = 418611600.

The previous prime is 680396641. The next prime is 680396657. The reversal of 680396649 is 946693086.

It is an interprime number because it is at equal distance from previous prime (680396641) and next prime (680396657).

It is not a de Polignac number, because 680396649 - 2³ = 680396641 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (680396641) 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 31 ways as a sum of consecutive naturals, for example, 2055414 + ... + 2055744.

It is an arithmetic number, because the mean of its divisors is an integer number (30660864).

Almost surely, 2^680396649 is an apocalyptic number.

680396649 is a gapful number since it is divisible by the number (69) formed by its first and last digit.

It is an amenable number.

680396649 is a deficient number, since it is larger than the sum of its proper divisors (300750999).

680396649 is an equidigital number, since it uses as much as digits as its factorization.

680396649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450 (or 388 counting only the distinct ones).

The product of its (nonzero) digits is 1679616, while the sum is 51.

The square root of 680396649 is about 26084.4139094594. The cubic root of 680396649 is about 879.5368814029.

The spelling of 680396649 in words is "six hundred eighty million, three hundred ninety-six thousand, six hundred forty-nine".