687843601 has 4 divisors (see below), whose sum is σ = 687896100. Its totient is φ = 687791104.

The previous prime is 687843581. The next prime is 687843619. The reversal of 687843601 is 106348786.

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 244109376 + 443734225 = 15624^2 + 21065^2 .

It is a cyclic number.

It is not a de Polignac number, because 687843601 - 2⁷ = 687843473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (687843661) 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, 11505 + ... + 38833.

It is an arithmetic number, because the mean of its divisors is an integer number (171974025).

Almost surely, 2^687843601 is an apocalyptic number.

It is an amenable number.

687843601 is a deficient number, since it is larger than the sum of its proper divisors (52499).

687843601 is a wasteful number, since it uses less digits than its factorization.

687843601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52498.

The product of its (nonzero) digits is 193536, while the sum is 43.

The square root of 687843601 is about 26226.7725997691. The cubic root of 687843601 is about 882.7340934303.

The spelling of 687843601 in words is "six hundred eighty-seven million, eight hundred forty-three thousand, six hundred one".