687919297 has 8 divisors (see below), whose sum is σ = 784415016. Its totient is φ = 597649152.

The previous prime is 687919283. The next prime is 687919327. The reversal of 687919297 is 792919786.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 42302016 + 645617281 = 6504^2 + 25409^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-687919297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (687919697) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1556158 + ... + 1556599.

It is an arithmetic number, because the mean of its divisors is an integer number (98051877).

Almost surely, 2^687919297 is an apocalyptic number.

It is an amenable number.

687919297 is a deficient number, since it is larger than the sum of its proper divisors (96495719).

687919297 is a wasteful number, since it uses less digits than its factorization.

687919297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3112787.

The product of its digits is 3429216, while the sum is 58.

The square root of 687919297 is about 26228.2156655766. The cubic root of 687919297 is about 882.7664733632.

The spelling of 687919297 in words is "six hundred eighty-seven million, nine hundred nineteen thousand, two hundred ninety-seven".