680707561 has 2 divisors, whose sum is σ = 680707562. Its totient is φ = 680707560.

The previous prime is 680707519. The next prime is 680707583. The reversal of 680707561 is 165707086.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 525555625 + 155151936 = 22925^2 + 12456^2 .

It is a cyclic number.

It is not a de Polignac number, because 680707561 - 2¹¹ = 680705513 is a prime.

It is not a weakly prime, because it can be changed into another prime (680707061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340353780 + 340353781.

It is an arithmetic number, because the mean of its divisors is an integer number (340353781).

Almost surely, 2^680707561 is an apocalyptic number.

It is an amenable number.

680707561 is a deficient number, since it is larger than the sum of its proper divisors (1).

680707561 is an equidigital number, since it uses as much as digits as its factorization.

680707561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 70560, while the sum is 40.

The square root of 680707561 is about 26090.3729563224. The cubic root of 680707561 is about 879.6708311751.

The spelling of 680707561 in words is "six hundred eighty million, seven hundred seven thousand, five hundred sixty-one".