688139102 has 16 divisors (see below), whose sum is σ = 1180684512. Its totient is φ = 294662400.

The previous prime is 688139083. The next prime is 688139113. The reversal of 688139102 is 201931886.

It is a congruent number.

It is an unprimeable number.

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, 3899 + ... + 37302.

It is an arithmetic number, because the mean of its divisors is an integer number (73792782).

Almost surely, 2^688139102 is an apocalyptic number.

688139102 is a deficient number, since it is larger than the sum of its proper divisors (492545410).

688139102 is a wasteful number, since it uses less digits than its factorization.

688139102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42403.

The product of its (nonzero) digits is 20736, while the sum is 38.

The square root of 688139102 is about 26232.4055702103. The cubic root of 688139102 is about 882.8604843046.

The spelling of 688139102 in words is "six hundred eighty-eight million, one hundred thirty-nine thousand, one hundred two".