687240497 has 4 divisors (see below), whose sum is σ = 687293220. Its totient is φ = 687187776.

The previous prime is 687240493. The next prime is 687240503. The reversal of 687240497 is 794042786.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 107827456 + 579413041 = 10384^2 + 24071^2 .

It is a cyclic number.

It is not a de Polignac number, because 687240497 - 2² = 687240493 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (687240493) 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, 9029 + ... + 38157.

It is an arithmetic number, because the mean of its divisors is an integer number (171823305).

Almost surely, 2^687240497 is an apocalyptic number.

It is an amenable number.

687240497 is a deficient number, since it is larger than the sum of its proper divisors (52723).

687240497 is a wasteful number, since it uses less digits than its factorization.

687240497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52722.

The product of its (nonzero) digits is 677376, while the sum is 47.

The square root of 687240497 is about 26215.2722091532. The cubic root of 687240497 is about 882.4760230708.

The spelling of 687240497 in words is "six hundred eighty-seven million, two hundred forty thousand, four hundred ninety-seven".