687580268561 has 2 divisors, whose sum is σ = 687580268562. Its totient is φ = 687580268560.

The previous prime is 687580268519. The next prime is 687580268579. The reversal of 687580268561 is 165862085786.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 532221316225 + 155358952336 = 729535^2 + 394156^2 .

It is a cyclic number.

It is not a de Polignac number, because 687580268561 - 2²² = 687576074257 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 687580268494 and 687580268503.

It is not a weakly prime, because it can be changed into another prime (687580268581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343790134280 + 343790134281.

It is an arithmetic number, because the mean of its divisors is an integer number (343790134281).

Almost surely, 2^687580268561 is an apocalyptic number.

It is an amenable number.

687580268561 is a deficient number, since it is larger than the sum of its proper divisors (1).

687580268561 is an equidigital number, since it uses as much as digits as its factorization.

687580268561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38707200, while the sum is 62.

The spelling of 687580268561 in words is "six hundred eighty-seven billion, five hundred eighty million, two hundred sixty-eight thousand, five hundred sixty-one".