687448397 has 4 divisors (see below), whose sum is σ = 727886556. Its totient is φ = 647010240.

The previous prime is 687448387. The next prime is 687448417. The reversal of 687448397 is 793844786.

687448397 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 289884676 + 397563721 = 17026^2 + 19939^2 .

It is a cyclic number.

It is not a de Polignac number, because 687448397 - 2¹⁰ = 687447373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687448337) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20219054 + ... + 20219087.

It is an arithmetic number, because the mean of its divisors is an integer number (181971639).

Almost surely, 2^687448397 is an apocalyptic number.

It is an amenable number.

687448397 is a deficient number, since it is larger than the sum of its proper divisors (40438159).

687448397 is a wasteful number, since it uses less digits than its factorization.

687448397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40438158.

The product of its digits is 8128512, while the sum is 56.

The square root of 687448397 is about 26219.2371551882. The cubic root of 687448397 is about 882.5650012711.

The spelling of 687448397 in words is "six hundred eighty-seven million, four hundred forty-eight thousand, three hundred ninety-seven".