686642880 has 336 divisors, whose sum is σ = 2768656896. Its totient is φ = 142571520.

The previous prime is 686642857. The next prime is 686642911. The reversal of 686642880 is 88246686.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (336).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 516777 + ... + 518103.

Almost surely, 2^686642880 is an apocalyptic number.

686642880 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686642880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1384328448).

686642880 is an abundant number, since it is smaller than the sum of its proper divisors (2082014016).

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

686642880 is a wasteful number, since it uses less digits than its factorization.

686642880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1372 (or 1355 counting only the distinct ones).

The product of its (nonzero) digits is 884736, while the sum is 48.

The square root of 686642880 is about 26203.8714696894. The cubic root of 686642880 is about 882.2201516456.

The spelling of 686642880 in words is "six hundred eighty-six million, six hundred forty-two thousand, eight hundred eighty".