687819752 has 8 divisors (see below), whose sum is σ = 1289662050. Its totient is φ = 343909872.

The previous prime is 687819733. The next prime is 687819791. The reversal of 687819752 is 257918786.

It can be written as a sum of positive squares in only one way, i.e., 674233156 + 13586596 = 25966^2 + 3686^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×687819752² = 946192022482683008, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 687819694 and 687819703.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42988727 + ... + 42988742.

Almost surely, 2^687819752 is an apocalyptic number.

It is an amenable number.

687819752 is a deficient number, since it is larger than the sum of its proper divisors (601842298).

687819752 is a wasteful number, since it uses less digits than its factorization.

687819752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85977475 (or 85977471 counting only the distinct ones).

The product of its digits is 1693440, while the sum is 53.

The square root of 687819752 is about 26226.3179268459. The cubic root of 687819752 is about 882.7238912232.

The spelling of 687819752 in words is "six hundred eighty-seven million, eight hundred nineteen thousand, seven hundred fifty-two".