687287745 has 12 divisors (see below), whose sum is σ = 1191298836. Its totient is φ = 366553440.

The previous prime is 687287717. The next prime is 687287749. The reversal of 687287745 is 547782786.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 287607681 + 399680064 = 16959^2 + 19992^2 .

It is not a de Polignac number, because 687287745 - 2¹⁶ = 687222209 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 687287691 and 687287700.

It is not an unprimeable number, because it can be changed into a prime (687287749) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7636486 + ... + 7636575.

It is an arithmetic number, because the mean of its divisors is an integer number (99274903).

Almost surely, 2^687287745 is an apocalyptic number.

It is an amenable number.

687287745 is a deficient number, since it is larger than the sum of its proper divisors (504011091).

687287745 is a wasteful number, since it uses less digits than its factorization.

687287745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15273072 (or 15273069 counting only the distinct ones).

The product of its digits is 5268480, while the sum is 54.

The square root of 687287745 is about 26216.1733477638. The cubic root of 687287745 is about 882.4962461086.

The spelling of 687287745 in words is "six hundred eighty-seven million, two hundred eighty-seven thousand, seven hundred forty-five".