687720087 has 6 divisors (see below), whose sum is σ = 993373472. Its totient is φ = 458480052.

The previous prime is 687720083. The next prime is 687720097. The reversal of 687720087 is 780027786.

It is not a de Polignac number, because 687720087 - 2² = 687720083 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 (687720083) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 38206663 + ... + 38206680.

Almost surely, 2^687720087 is an apocalyptic number.

687720087 is a deficient number, since it is larger than the sum of its proper divisors (305653385).

687720087 is a wasteful number, since it uses less digits than its factorization.

687720087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76413349 (or 76413346 counting only the distinct ones).

The product of its (nonzero) digits is 263424, while the sum is 45.

The square root of 687720087 is about 26224.4177628408. The cubic root of 687720087 is about 882.6812536349.

The spelling of 687720087 in words is "six hundred eighty-seven million, seven hundred twenty thousand, eighty-seven".