686971776 has 64 divisors (see below), whose sum is σ = 1845363600. Its totient is φ = 226406400.

The previous prime is 686971763. The next prime is 686971781. The reversal of 686971776 is 677179686.

It is a tau number, because it is divible by the number of its divisors (64).

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, 24126 + ... + 44226.

Almost surely, 2^686971776 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686971776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (922681800).

686971776 is an abundant number, since it is smaller than the sum of its proper divisors (1158391824).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

686971776 is a wasteful number, since it uses less digits than its factorization.

686971776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20207 (or 20195 counting only the distinct ones).

The product of its digits is 5334336, while the sum is 57.

The square root of 686971776 is about 26210.1464322502. The cubic root of 686971776 is about 882.3609877687.

The spelling of 686971776 in words is "six hundred eighty-six million, nine hundred seventy-one thousand, seven hundred seventy-six".