687511481 has 2 divisors, whose sum is σ = 687511482. Its totient is φ = 687511480.

The previous prime is 687511421. The next prime is 687511519. The reversal of 687511481 is 184115786.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 414733225 + 272778256 = 20365^2 + 16516^2 .

It is a cyclic number.

It is not a de Polignac number, because 687511481 - 2⁶ = 687511417 is a prime.

It is a super-2 number, since 2×687511481² = 945344073013626722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (687511421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343755740 + 343755741.

It is an arithmetic number, because the mean of its divisors is an integer number (343755741).

Almost surely, 2^687511481 is an apocalyptic number.

It is an amenable number.

687511481 is a deficient number, since it is larger than the sum of its proper divisors (1).

687511481 is an equidigital number, since it uses as much as digits as its factorization.

687511481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53760, while the sum is 41.

The square root of 687511481 is about 26220.4401374195. The cubic root of 687511481 is about 882.5919967653.

The spelling of 687511481 in words is "six hundred eighty-seven million, five hundred eleven thousand, four hundred eighty-one".