687881566 has 16 divisors (see below), whose sum is σ = 1090117440. Its totient is φ = 325013920.

The previous prime is 687881561. The next prime is 687881587. The reversal of 687881566 is 665188786.

It is a super-2 number, since 2×687881566² = 946362097685224712, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687881561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 123445 + ... + 128896.

It is an arithmetic number, because the mean of its divisors is an integer number (68132340).

Almost surely, 2^687881566 is an apocalyptic number.

687881566 is a deficient number, since it is larger than the sum of its proper divisors (402235874).

687881566 is a wasteful number, since it uses less digits than its factorization.

687881566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252419.

The product of its digits is 3870720, while the sum is 55.

The square root of 687881566 is about 26227.4963730814. The cubic root of 687881566 is about 882.7503337420.

The spelling of 687881566 in words is "six hundred eighty-seven million, eight hundred eighty-one thousand, five hundred sixty-six".