687732449 has 2 divisors, whose sum is σ = 687732450. Its totient is φ = 687732448.

The previous prime is 687732443. The next prime is 687732469. The reversal of 687732449 is 944237786.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 627001600 + 60730849 = 25040^2 + 7793^2 .

It is a cyclic number.

It is not a de Polignac number, because 687732449 - 2⁸ = 687732193 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 687732397 and 687732406.

It is not a weakly prime, because it can be changed into another prime (687732443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343866224 + 343866225.

It is an arithmetic number, because the mean of its divisors is an integer number (343866225).

Almost surely, 2^687732449 is an apocalyptic number.

It is an amenable number.

687732449 is a deficient number, since it is larger than the sum of its proper divisors (1).

687732449 is an equidigital number, since it uses as much as digits as its factorization.

687732449 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2032128, while the sum is 50.

The square root of 687732449 is about 26224.6534581489. The cubic root of 687732449 is about 882.6865424341.

The spelling of 687732449 in words is "six hundred eighty-seven million, seven hundred thirty-two thousand, four hundred forty-nine".